You can't go wrong with these games:
All of these are 4-players and are on the N64. These games are REALLY fun to play with your friends at a party or something.
-Goldeneye 007
-Perfect Dark
-Mario Kart 64
-Super Smash Bros.
-WWF No Mercy (if you're into pro-wrestling)
-NBA Hangtime (almost exactly like NBA Jam)
-Mario Party (any of them): Playing with 4 human players eliminates having to deal with the very cheap computer players, which in turn makes the game more fun.
-Mario Golf, Mario Tennis
-And a whole bunch of other N64 games, but those are the ones that I enjoy the most.