Mine are:
Atari - never actually owned the game, but played it after and it's H.E.R.O. Very modern game for its time.
Master System - Alex Kidd in Miracle World
NES (called Phamtom System here) - Super Mario Bros 3
Genesis - Toe Jam & Earl / Sega CD: Sonic CD
SNES - Super Mario World
Game Gear - Streets of Rage 2
Gameboy - Only had one game so, by default... Pokémon Yellow
Dreamcast - Mars Matrix and Giga Wing
PS2 - Metal Gear Solid 3
Gamecube - The Legend of Zelda - The Wind Waker
DS - Hard to choose but a tie between New Super Mario Bros and Animal Crossing
Wii - Had it just for a short period and didn't played it much, but New Super Mario Bros Wii
PSP - Megaman (s) and Ultimate Ghouls and Ghosts
3DS - Mario 3D Land.. no... Kid Icarus... no, 3D Land... no, Kid Icarus....TIE!!!!
And N64: The Legend of Zelda - Ocarina of time. Best overall too.
