I like the big epics: The Uncut Stand, It, Needful Things. The little nasties are also good: The Shining, Misery, Pet Semetery.
As has been said by literally everyone else in this thread, he's good at getting a big story going and not very good at wrapping it up.
The three big epics that I like, I enjoy despite the deus ex machina nature of the endings.
I'm thinking out loud here but part of what makes a book like The Shining or Misery work is that there's a very limited cast (four people and two people, respectively) and a very limited set (Annie's house and The Overlook). So at the end, either they're going to die or they're not and either they're going to escape or they're not and either the place gets destroyed or it doesn't. King works well inside that box.
A little known fact about King is that when he was little he went to play at a friend's house and there was a train track in the back yard and he saw his friend get absolutely creamed by the train. That would fuck a person up.
Oh, and nobody has mentioned Eyes of the Dragon. That book is tits.