Maleficent's my favorite Disney baddie. Shere Khan's a close second.
Also, the lady who did her voice also was Cinderella's stepmother. Despite the lack of evil powers granted by Satan, she's was pretty evil too.
Yes, "hell". It's a nothing word for us today, but think about its impact on parents and children when the movie came out. That must've bordered on scandalous at the time. Just as many people were up in arms over "shit" and "damn" being said in Transformers: The Movie.
Which begs the question...Maleficent versus Megatron...