Zelda is pretty damn fun but there are defintely a couple of other cool games out. Excite Truck is a lot of fun. I rented it and it seemed really simple at first but there are a ton of little tricks that you can master which make it really fun.
Also, they are starting to put out some decent Virtual Console games. Street Fighter II: The World Warrior is on there now and so is a Castlevania, which I've always loved. Apparantly new games are released on Mondays.
If anyone is looking for awesome 4-player action, I HIGHLY recommend downloading Bomberman. Man o man that game is insanely fun.