I never really considered Mario Kart to ever really be a co-op game (except double dash).
We play the balloon battle multiplayer, and play on the same team.. That way we're not competing against each other (I'm 35, she's 8) and work together.. We've had so much fun with it I'm thinking of buying another couple of NDSLs for my wife and son (4) so we can all play..
QUOTEIf you mean multiplayer, then there's stuff like Tetris, New Super Mario Bros minigames and Bomberman.