Mine would have to be
The Legend of Zelda: The Wind Waker
Metroid Prime
Super Mario Galaxy
Fallout 3
The Elder Scrolls IV: Oblivion
Paper Mario: The Thousand-Year Door
Pokemon Gold, Silver, Crystal
Resident Evil 4
The Legend of Zelda: Majora's Mask
Half-Life 2
Portal
Mario and Luigi: Bowser's Inside Story
BioShock
Call of Duty 4: Modern Warfare
Shadow of The Colossus
Paper Mario
Advance Wars: Dual Strike
Ico
Mario and Luigi: Super Star Saga
Team Fortress 2
Mario Kart DS
Mario and Luigi: Partner's in Time
Rock Band 2