Trivial Pursuit is one of my all-time favorites. Scrabble is fun, though I usually modify the rules (bonus points for geeky words, and names are allowed if they are cool/obscure enough. Also, J is way too hard to use, much harder than Z, since it almost always occurs at the beginning of a word, and Q really needs to be Qu). Oh, and I recently did a revamp to the rules of Clue that makes the game quite a bit better overall.