Not counting gifts or games that came with the systems:
NES: Double Dragon II
Sega Genesis: Sonic 2
Sega 32X: Zaxxon's Motherbase 2000
Sega CD: Cliffhanger
Gameboy: Super Mario World 2
Gameboy Color: Metal Gear Solid
Nintendo 64: Super Mario 64
PS2: Castlevania: Symphony of the Night
Gamecube: Mario Party 7
GBA: Castlevania: Circle of the Moon
Dreamcast: Sword of the Berserk
Xbox 360: Dead Rising
PS3: Demon's Souls
Nintendo DS: Feel the Magic XX/XY
PSP: Bomberman
PC: Diablo