Little Big Planet 2! I swear, I have never had so much fun with my non-gamer friends as we have had while playing LBP2. Not only that, it's a pretty creative and cutesy game. Of course it's lacking the testosterone protagonist of GoW, the adventurous Drake from Uncharted, or any actual protagonist for that matter, but the game really lets your imagination run rampant!
There is literally something for everyone in the game, if you're into competitive play the score boards are a great way to test your mettle. I can't describe how satisfying it is to score in the top 1% on a story level.