I still enjoy Woody Allen's work and I still love the movie Chinatown, by Polanski.
In fact, I've been listening to Gary Glitter on my gym ipod and he's been accused of pedophilia. Sometimes the lyrics can sound creepy in retrospect, but I still dig the music.
It doesn't mean I condone the things they are infamous for. I just dissociate their private lives from the work.
A different scenario for me is Leni Riefenstahl's work. Great photography, but her films were pure Nazi propaganda. I cannot dissociate the work from the artist here because it's the very content of her work and I never bought the angle that she was na´ve and didn't know what she was doing.