5th generation, hands down. The leap from 2D to 3D is massive, the most revolutionary jump in hardware tech in gaming. I can't think of any game that WOWed me more than playing Super Mario 64 for the first time. I love 2D games as much as the next guy, trust me, I'm probably more of a 2D gamer at heart, but N64 and PS1 were the most impressive systems of their respective time. No other consoles pushed the boundaries of the generation it was from more than those. Sure 3D PC games may have existed at that time but for console gamers, this was huge. I will always think of N64 as the first modern system since it was the system that heralded in the analog stick and rumble pack, 2 things that are standard features nowadays, plus all consoles of that generation used 3D, and N64 especially really pushed it and focused on it. Ever since the 5th gen 3D gaming has been the standard. On top of that, 4 controller ports focused more on multiplayer, which is also huge today, even if most multiplayer is done mostly online, N64 was the first to really focus on it. If you look at today's standard features in games and consoles, a lot of the biggest ones got their start in the 5th gen, N64 being the biggest influencer, I think. I am sure many will disagree, and that's fine, but this is how I see it.