Oi, this is my wheelhouse. I used to have a VGM YouTube channel.
Chrono Cross
Final Fantasy IX, X
Shadow of the Colossus (I also like ICO, specifically the save theme)
Drakengard (pure chaotic bliss)
God of War
Wild Guns
Guilty Gear X (Arcade & Dreamcast/PS2)
Mega Man 2 (somewhat overrated, but still great), 3, 9
Mega Man X (any, but X, X2, X3, and Command Mission are top favorites)
Mega Man X7 (not particularly fond of the game, but I do enjoy the soundtrack)
Mega Man X3 (PS1/Saturn version)
Einhänder
Contra (III, Operation C, and Neo are top favorites)
Super Mario Land 2: 6 Golden Coins
Kingdom Hearts
Kingdom Hearts II
Super Metroid
Metroid Prime
The Legend of Zelda: Link's Awakening
The Legend of Zelda: A Link to the Past
Command & Conquer
Command & Conquer: Red Alert
StarFox (SNES & N64)
Super Mario 64
Teenage Mutant Ninja Turtles: Turtles in Time (Arcade & SNES)
Batman Returns (SNES)
The Simpsons Arcade Game
Killer Instinct: Killer Cuts
Pokémon GRBY, GSC, Emerald
Pokémon Battle Revolution
Axelay
Castlevania (tough to decide)
Armored Core (4 and for Answer are top favorites)
Burning Force (Arcade)
Streets of Rage
BlazBlue: Calamity Trigger (Arcade)
Zombie Daisuki
Metal Gear Solid
Metal Gear (MSX)
Ollie King
Rez
Godhand
Hokuto no Ken (Arcade/PS2)
Shatterhand
Street Fighter 2010: The Final Fight
Ikari Warriors (Arcade)
Jak X: Combat Racing
Mario Kart DS
Speed Racer: The Video Game (Console)
Tetris (Game Boy)
Kirby's Pinball Land
Metal Slug 3, X
Biker Mice from Mars (SNES)
Cyber Troopers
DOOM (DOOM 2016 is quite good, great for working out)
Donkey Kong Country
Gotcha Force
Street Fighter II (Arcade)
X-Men: Children of the Atom
X-Men VS. Street Fighter
Marvel Super Heroes VS. Street Fighter
Soul Calibur II
Space Invaders Extreme
No More Heroes 2: Desperate Struggle
Mega Man Zero (Remastered Tracks)
Sin & Punishment
Sin & Punishment: Star Successor
Viewtiful Joe
Sub Rebellion
X-Men: Mutant Apocalypse
Yu-Gi-Oh! Forbidden Memories (haven't really played the game, but gave the soundtrack a listen and liked it quite much)
Luigi's Mansion (I love Luigi's humming)
Low G Man
Gradius (any, same with Darius)
Mobile Suit Gundam (any of the PS2 games since they re-use music from the series)
So on and so forth. I can do this all day.