They're almost all in a long line of chick flicks, the most recent humiliation being "Ghosts of Girlfriends Past", the original being Titanic.
I also watch a lot of kids movies, and I don't have kids. They're Sunday afternoon hangover fair, but I am somewhat embarrassed. Think Ice Age, Harry Potters, The Golden Compass, Narnia, etc...
I watch dumb movies too, but Im not really ashamed of them. Like Dorm Daze, Road Trip 2..whatever.