Happy or sad is good. Disappointed, angry or indifferent is bad.
I must admit that I prefer happy to sad but the other feelings are in a different category. Anything that comes under the heading 'unsatisfied' can spoil the whole story for me.
Satisfying story endings that I have come across recently include Son of Rambow, which I saw last night. It was a very enjoyable film and the ending felt satisfying. If it hadn't, for me it would have spoilt the entire film.