I had to think about these for a while, and this list may change the more I look at it. These were some tough choices.
2nd Generation:
-The Swiss Family Robinson (Commodore 64) - In 6th grade, I was 11 years old and it was 1994. But we still had Commodore 64s in our classroom at the Christian school I attended. At that school, 6th grade was the last elementary school grade, so we still had recess. A few of us opted to stay inside rather than play on the playground and we tinkered around with the Commodore 64s. The game we all played the most, as we figured out the puzzles together in person, was Swiss Family Robinson. A great, graphical text-adventure full of item-puzzles and traps.
-The Oregon Trail (Apple II) - Before 6th grade, I was at the local public school. There in the library computer lab, they had Apple IIs (some originals, some IIe's, some IIGS's, it was a mixture). So my favorite game they had on it, like many kids of our generation, was Oregon Trail. The hunting was the best part of the game; my wagon always had plenty of meat.
-Missile Command (Atari 2600) - My personal favorite Atari 2600 game. I know purists think it's blasphemy because you need the trackball. Well, I never played the arcade. So the Atari 2600 version with a Sega Genesis controller does just fine for me. Very simple, yet addictive gameplay here.
3rd Generation:
-Super Mario Bros. 3 - I'm sure this is on many lists. It may be a clichéd choice, but there's a reason. This was a spectacular game when it was released. Nothing could touch it. Sure, Sega Genesis and TG-16 had better graphics, but no other platformer at the time could touch the gameplay on this one. And for an NES game, it was one of the best looking ones!
-The Legend of Zelda - The adventure begins here. Oh man, in the days before the internet, I spent hours upon hours scouring the original land of Hyrule for that next secret I had missed. I know younger people may just see this as some rudimentary-looking, archaic predecessor to the later Zelda games, but when this game came out, it was literally a game-changer. There was nothing else like it at the time. Just the size, scope, and epicness of it all was beautiful to behold.
-Bionic Commando - The NES version in particular (which was very different from the arcade/Capcom Classics version) was an action-platforming masterpiece. Capcom really outdid themselves with this game. I still whip it out and play it from time to time. The swinging mechanics do take a minute to get used, but once you do understand how it all works, the controls are spot-freaking on and you will be swinging around better than Spider-Man himself. The story is really cool, too. Obviously the red army is a loosely-veiled cover for the resurrection of the Nazis. The U.S. Army sends out their top man, Super-Joe to infiltrate enemy territory and stop their secret weapon from completing; but he gets captured. They send you in, a bionically augmented super-soldier, to rescue Super-Joe and help him finish his mission.
4th Generation:
-Super Mario World (SNES) - So much fun. That's the best way to describe this game. IMO, this is pure-platforming, 2D perfection. After all these years, I STILL want a direct-sequel to this game (and no, Yoshi's Island doesn't count, it's only a sequel in name). The controls were perfect, the level design was sublime, and music was fantastic and fit perfectly for this game, and the graphics were a perfect mixture of 16-bit "show-off" and cartoonyness.
-The Legend of Zelda: A Link to the Past (SNES)- The greatest Zelda game ever made, bar-none. A gaming masterpiece that has yet to be improved up on in the series, as far as I'm concerned. I've played this game so much I can play it with my eyes-closed.
-Super Metroid (SNES) - Just like Link to the Past, this game has yet to be improved upon in it's series, as far as I'm concerned. This was and is the best Metroid ever made. So atmospheric, and such a cool emphasis on exploration. Throw in some great platforming, music, and boss-battles and it never gets dull while exploring, either.
5th Generation:
-Resident Evil 2 (PS1) - Still the best game in the series, IMO. Best story, for sure. The plots and twists, and reveal of new creatures (that intro scene for The Licker was bad ass and reminded me so much of Venom when I first saw it) made this game awesome. And the setting of a zombie-infested city was great for the horror fan in me (I grew up on horror, thanks to my dad). I especially have always loved zombies films like Dawn of the Dead, Day of the Dead, and Return of the Living Dead. So this game was a real treat. And I got it with my original PlayStation, so I played it before I ever played the first game in the series. Luckily, RE2's storyline stand-enough on it's own that I wasn't confused. The characters aren't the same in the 2 games, and the connection between the 2 games is explained to you in the game.
-King's Field II (King's Field III in Japan) (PS1) - It's not a popular series. And was pretty much entirely unknown until Dark Souls came out. But I was that one guy that bought it on the bargain rack at Electronic Boutique. And when I brought it home, I immediately died. Once I learned to take the game a little slower, I found an immensely large world to explore and grow in. I can't think of another game so seamlessly huge on the PS1. In many ways, this was the series that was a precursor to the Elder Scrolls games for me (I didn't play one of those until Morrowind on the XBox). One of my favorites to this day that I still pull out and play every once in a while (which usually leads to playing through the entire series, this games predecessor and a sequel on PS2).
-Castlevania: Symphony of the Night (PS1) - As you can see with my Super Metroid pick, I love me some Metroidvania. Symphony of the Night wasn't the first foray into that formula (Castlevania II: Simon's Quest on NES was), but this was the first one to really catch and set the tone for the Castlevania series for years to come. And there's good reason why. This was a 2D masterpiece. Such fantastic 2D graphics, great exploration-based gameplay with cool boss-battles, and fan-freaking-tastic music. Konami at their finest here.
6th Generation:
-Halo 2 (XBox Original) - I know, most Halo fans would pick Combat Evolved, but not me. The biggest draw for me in Halo is the sci-fi storyline. And I REALLY liked the story in Halo 2. It felt like a blockbuster sci-fi movie being told to me, in game form, and it was fantastic! I loved that you got to see both Master Chief's and The Arbitur's point-of-views, that really helped the story stand-out for me. And the production values for an original XBox game were phenomenal! Amazing graphics and set-pieces, and the sound-effects and musical-score that accompanied it all were like ear-candy.
-Metroid Prime (GameCube) - Metroid gets mentioned a few times on this list. I REALLY like the Metroid series. It took me a while to warm up to this one, though. I felt betrayed that my beloved Metroid series was no longer in 2D. Once I played the game, though, I discovered a beauty of a game. The graphics were gorgeous, and the soundtrack was phenomenal. And the gameplay, while I still prefer 2D Metroid, was a blast to play. The upgrades kept me looking in every nook and cranny. That moment when I stepped out onto the Pheandra Drifts area (the snow area) and heard that atmospheric, wintery music playing, and saw those fluorescent dragonfly-things gliding in the air, was a moment of art for me and made me just stop and take a deep breath and let it all in as I looked around. Moments like that are why some video games should be considered a form of art.
-Neverwinter Nights (PC) - I'm an action-RPG junkie. I can't get enough of them. And this was the best point-n-click action-RPG I've ever played. It feels a lot like Baldur's Gate: Dark Alliance while playing, but with much more fleshed-out RPG elements, a bigger world, and better production values. Just an immense game that explores all over Forgotten Realms where there's a ton of enemies, dungeons, towns, items, and spells to uncover. This game kept me busy for a VERY long time.
7th Generation:
-The Elder Scrolls IV: Oblivion - Game of the Year Edition (XBox 360)- My all-time favorite Elder Scrolls game. Most people prefer Skyrim, which is a fan-freaking-tastic game, too, but I thought this one was a tad better. There were a bit more RPG elements, and lot less dragon battles interrupting you from your questing. And while there were glitches, not nearly as many as I encountered in Skyrim. Morrowind blew me away with the amount of detail and it being such a freaking huge game at the same time; but this game improved on everything Morrowind did. Bigger game, better graphics, better sound, and best of all: More variety in character, enemy, and environment designs.
-Batman: Arkham City - Game of the Year Edition (XBox 360)- Arkham Asylum was great, too, don't get me wrong there. But the open city feel of this game really hammered in that Batman feel from the comic books. Arkham Asylum already got the look, sound, and movement of Batman down to a "T", as his enemies. But Arkham City got the environment and atmosphere just as evenly matched. A masterpiece that MUST be played by any Batman or comic book fan.
-Bionic Commando (XBox 360) - This is a game I had to play twice to appreciate. The first time I got it, I paid a bit more for it and I was a new XBox 360 owner. So I got stuck, I got frustrated, and instead of being patient with the game I took it back and got another game to try out on my shiny new XBox 360. Flash-forward a year or two and I see it in the bargain bin. Like $5 complete bargain bin. So I get it and give it another try. This time I'm not like a kid with a new toy so I give the game more time and patience, and it turns out to be THE hidden gem of the generation for me. I LOVED the swinging mechanics and plethora of grapple-moves you can unlock through-out the game. It was a blast to just swing through areas like Spider-Man while shooting an enemy, then dropping down on top-of him like pissed-off Superman!
Handhelds:
Game Boy/Game Boy Color/NGPC: (I have a Game Gear, too, but none of those games made the cut for me.)
-Super Mario Land 2: The 6 Golden Coins (Original GB) - The best handheld Mario game until New Super Mario Bros. came out on DS. It's very reminiscent of Super Mario World with the overmap, but in the actual levels plays more like Super Mario Bros. 3. So you get a little pocket version of some of the best parts of both games. And this game introduced Wario as the Mario's main-enemy.
-The Legend of Zelda: Link's Awakening DX (GBC) - This isn't just a good Zelda game for a handheld, it's a good Zelda game that's so good it can stand shoulders-to-shoulders with it's full console counterparts. Great Zelda game full of exploration, great music, cool boss battles, and the dungeons we all love. The DX version (GBC version) in particular is the one to get as it has color (duh) and smoother scrolling, as well as an entirely new dungeon. It also has Game Boy Printer supports, if anyone still has a working Game Boy Printer.
-Sonic Pocket Adventure (NGPC)- I still think this is the best Sonic handheld game ever made. It plays VERY similarly to the Genesis Sonic games, which is a great thing. And it looks spectacular for a NGPC game.
GBA:
-Metroid: Zero Mission - This is a complete remake of the original Metroid for NES, made from the ground-up with Metroid: Fusion style controls and graphics. It's really tough to say if this is the greatest game remake ever, because Resident Evil on GameCube was pretty damn well remade, too. But it's definitely #2 if it's not #1.
-The Legend of Zelda: Minish Cap - My favorite Zelda game after Link to the Past for SNES. I must admit, I wasn't a fan of the more cartoony looking graphics this Zelda game sports. But once I got past that, I really dove into the game. Lots to do in this Zelda game besides just the main-quest, which is also awesome. Some people say the shrinking mechanic is just a cheap gimmick, but I thought the "Minish" world, when you shrink down, really adds a whole new layer to the game; much like The Dark World did in Link to the Past and Link Between Worlds.
-Golden Sun/Golden Sun: The Lost Age - I know, that's cheating. But really, they are two directly-connecting games to form 1 game, like Sonic the Hedgehog 3 and Sonic & Knuckles on Genesis. The 1st game ends on a cliffhanger, and the 2nd game picks-up directly where the 1st game ends; with the first game never having solved the main problem. Great little traditional-style JRPG with an engaging storyline and characters. Perfect for whittling away some time on your GBA, too. It comes in handy for grinding when you just have a few minutes here or there to kill and you have a GBA-SP in your pocket.
Nintendo DS: (Still don't have a PSP, but I so want one)
-New Super Mario Bros. - The return of 2D-platforming Mario games, HOORAY! Mario was always at his best in 2D, and this game delivers all the joys and delights of the old-school games all over again. I couldn't have been a happier old-school Mario fan when this game out. It drove me to go out and get a DS.
-Super Scribblenauts - If you can spell it, you can use it in this game. Practically anything you can think of (that's appropriate for your grandma to hear) can be created and used in this game. It's like a digital toy-box of endless stuff to play with!
-Ninja Gaiden: Dragon Sword - Very fun Ninja Gaiden game that makes great use of the screen and touch-screen controls. You can tilt the screen on it's side for a wider view. And all attacks and moves are done with the touch-screen controls. I know that sounds tedious, but it's done very well and feels very satisfying. But dang does it do a number on your screen if you aren't careful.
Nintendo 3DS: (Don't have a PS Vita)
-The Legend of Zelda: Link Between Worlds - A direct sequel to The Legend of Zelda: A Link to the Past on SNES some 20 years earlier. And this was the most fun I've had with a Zelda game in a VERY long time (console releases included). Don't get me wrong, I enjoyed Phantom Hourglass, but this game just completely blows it out of the water (see what I did there?). If you've played Link to the Past, many things will seem familiar here (which is a good thing) but there's so much new here it's not the same game at all. A great nostalgic romp to the past and a great new Zelda experience at the same time. This is what made me buy my 3DSXL.
-Super Mario 3D Land - Great Mario game that feels a little like a 2D Mario game despite it being a 3D one. It has a lot of the traditional stuff from the 2D Mario games, but put into 3D levels (that you DON'T have to repeat 10 times!). Great buy for any Nintendo fan.
-New Super Mario Bros. 2 - Take the great 2D resurrection of Mario that was New Super Mario Bros. on DS, and sprinkle in a little Wario-esque coin-greediness, and you have New Super Mario Bros. 2. Lots of people complain that it's too similar to past 2D Mario games...why are you people complaining like that's a bad thing?! Besides that, I felt the coin-collecting total count and level-completion added enough of a new layer to the game to give a little different feel in the gameplay from past 2D Mario games, if you were actually looking for a high coin count (I was).