I'm trying to figure out how Wii Sports isn't on this list......
Wii Sports completely set the tone for the Wii's success. The game was so well balanced with what consumers wanted out of the system that it created the issue that many Wii owners never bought another game. You really can't have a more successful launch game than that.
Greatness Awaits
PSN:Forevercloud (looking for Soul Sacrifice Partners!!!)