I wouldn't say this movie is scary but it's just fascinating. Basically, it has appeal because the things driving the caretaker to insanity could happen to anyone. It's simply a man having his weaknesses played upon - leading to a tragic end.
Anyway, the hotel is a big star, by itself, as it's a really creepy looking place.
However, Stephen King, himself, didn't like the popular movie adaptation seeing Jack Nicholson as being predictable too early on in the movie - not to mention he was already associated with being crazy (One Flew Over the Cuckoo's Nest etc..)
I think with the Shining, you have a isolation thing going on with this guy, and Jack Torrence who is a writer, but has to support his family and look after the Overlook Hotel for the winter. The combination of isolation, monotony, creative frustration, and supernatural forces extract Jack's insanity.
I never viewed this as a horror film. It was always just suspense or thriller to me. Like mentioned it just shows how the mind can break down in isolation and repetition.
