I realize not everyone has a game they like but are ashamed of, but there's gotta be at least a few.
I've got a few, but the top one(s) would have to be the pokemon series
. When the first two came out big groups of people would battle and trade and such in the cafeteria at lunch, so it wasn't like I was a dork for playing or anything. They were fun games and still are, but I just play the newest one on an emulator now.