Mommy dearest .... My mother was a "touch" mad so that movie strikes a nerve in me :) though it's a bit tame by comparison :) I like the Carrie movie though aswell :)
I haven't seen either and I have no intention of seeing either.
I m going to say Mommie Dearest. Only because it was supposedly a true story.
I've seen them both (although a long time ago). To me, you seem to be comparing apples to oranges. One is supposed to be a real life story, and one fiction. Neither is a movie I would watch again.