Though it's been a few years since I've read it, I recall it very well. There are a few bumpy parts and I think your "Scooby Doo Gang" description is perfect. They did kind of blunder their way through the book, but hey, no one is perfect.

I think King writes flawed characters better than anyone, and he loves letting them have a chance at redemption (see Callahan coming back in the Dark Tower books). But what King really excels at is writing about kids, and/or from a kids point of view. He touched on that a little here, and it gets better as he progresses as an author. You'll see that as you start The Shining.