Monopoly -- I'm surprised no one has mentioned yet that there's no strategy. Buy everything you land on.
Pictionary -- It's more fun when you make up the cards yourself.
Sorry -- We tried to make it more interesting by letting you hold a hand of cards and drawing them rummy style, but then everyone started hoarding Back 4 cards to sneak their pieces from home to right in front of your goal, and then it sucked again.
I have some personal bad experiences with getting my throat stepped on in Age of Renaissance and Metro, but that doesn't make them necessarily bad games.