Dislike them both. Maybe I have a weird sense of humor, but they do not amuse me at all. I don't watch much TV at all though, so my entertainment lies in different things than most anyways. I just don't get a kick out of those crude shows, not that the language offends me it's just that it doesn't make me laugh.
I HATE Family Guy. Like, unreasonably so. I find it so irritating, and like it's just a Simpsons knock off, filled with gags that have nothing to do with the story, and are there just to get quick, simple, cheap laughs, and they aren't even funny. It completely lacks creativity and originality.
South Park is okay. They have some funny episodes, and some that are kind of meh. Overall, I enjoy it, though.