NES - Super Mario Bros.
SNES - Super Mario World
Genesis - Sonic the Hedgehog
N64 - Goldeneye 007 (probably the toughest for me to answer. Mario 64 and Ocarina of Time are both close runners up.)
Saturn - Virtua Fighter
PlayStation - Crash Bandicoot
Gamecube - Super Smash Bros. Melee
Dreamcast - Soul Caliber (People saying Shenmue are crazy.)
PlayStation 2 - Grand Theft Auto: San Andreas
Xbox - Halo: Combat Evolved
Wii - Wii Sports
PlayStation 3 - Uncharted 2: Among Thieves (GT5 and God of War 3 were bigger deals when they came out, but I don't think they are remembered in the same way.)
Xbox 360 - Grand Theft Auto V (Gears of War for exclusives)
Wii U - Splatoon
PlayStation 4 - Uncharted 4
Xbox One -
Game Boy - Tetris
Game Boy Advance - Pokemon Ruby/Sapphire
Nintendo DS - Nintendogs
Nintendo 3DS - Fire Emblem Awakening (Obviously not the biggest game on the system, but it made this franchise more relevant in the west than anyone thought it would ever be.)
PSP - Monster Hunter Portable 3rd
Vita - Persona 4 Golden
SNES - Super Mario World
Genesis - Sonic the Hedgehog
N64 - Goldeneye 007 (probably the toughest for me to answer. Mario 64 and Ocarina of Time are both close runners up.)
Saturn - Virtua Fighter
PlayStation - Crash Bandicoot
Gamecube - Super Smash Bros. Melee
Dreamcast - Soul Caliber (People saying Shenmue are crazy.)
PlayStation 2 - Grand Theft Auto: San Andreas
Xbox - Halo: Combat Evolved
Wii - Wii Sports
PlayStation 3 - Uncharted 2: Among Thieves (GT5 and God of War 3 were bigger deals when they came out, but I don't think they are remembered in the same way.)
Xbox 360 - Grand Theft Auto V (Gears of War for exclusives)
Wii U - Splatoon
PlayStation 4 - Uncharted 4
Xbox One -
Game Boy - Tetris
Game Boy Advance - Pokemon Ruby/Sapphire
Nintendo DS - Nintendogs
Nintendo 3DS - Fire Emblem Awakening (Obviously not the biggest game on the system, but it made this franchise more relevant in the west than anyone thought it would ever be.)
PSP - Monster Hunter Portable 3rd
Vita - Persona 4 Golden