i agree w/ the rayman recommendation.
i was torn about getting rayman or super monkey balls based on how everyone was praising both of them.
rented monkey balls over thanksgiving weekend, think all of the mini games are playable w/o the need to unlock. some of the games are fun, some are hard and it'll get you frustrated ( = not fun if you guys are drunk)...and single player for me just sucked, looked like the same thing over and over again, just different background/stages.
i bought rayman like 2 weeks ago, like 2/3 finished w/ the story mode, but i love the minigames they have, it's hilarious and definately worth it for the fun factor w/ friends until Mario Party comes out next year