Thank you for the suggestions everyone!
She is far from being a wreck, that's or sure! (Or at least I hope she is!) I know well that the 'hitting' method doesn't fix things.Often times I just show her the accident, and try to talk to her, saying 'bad!' and putting her in the right place.
I like the leash idea a lot. I think we'll try that.
I'll keep checking in here. Thanks everyone.