I am trying to find the name of an animated movie that was played on HBO in the early 80s. I don't remember much about the story, but from what I remember there was a woman that was like a witch and her son was like a Frankenstein type character. The woman had a magic box or something that would play music I think. I think that there was also a young girl in it that the son was in love with and she was kept prisoner in the woman's castle. I know that this sounds very vague but it is all that I can remember. If anyone could help I would appreciate it. :)

Could it possibly be jack and the beanstalk. It's a japanese anime made in 1974.