Rayman Raving Rabbids doesn't require much skill, but is really fun. I have only played the first one and you should be able to get it pretty cheap. It has lots of mini games that are short, and use the wii controls in many different ways. Wathching the rabbids dance would only get funnier as you kept drinking. It has lots of different styles of games, and many of them are shorter than a minute or even 30 seconds. That is real important becasue when you are drunk you dont want to sit there and be playing something like twilight princess. I have heard pretty good things about Wario Smooth Moves too.
Super Smash Brawl is good for any and every occassion though.