SNES: Super Mario world
N64: Zelda Ocarina of Time
GC: Metroid Prime or Zelda Wind Waker (can never decide)
Wii: Zelda Twilight Princess or Metroid Prime 3 (perfect controls imo)
GBC: Pokemon Yellow
GBA: Golden Sun 1 and 2 or Fire Emblem
DS: 9 hours, 9 persons, 9 doors
PS1: Rayman 2 or Crash Bandicoot 2 and 3
PC: Bioshock or Portal 1 and 2 (I know this aren't exclusive but I don't own a 360 or PS3)
Nintendo and PC gamer