I'm not much of a King fan, with the notable exceptions of Salem's Lot and Firestarter. I really enjoyed The Stand, but wasn't able to get into it again. The others I read didn't grab me the same way, though, and more than a few I returned to the library unread. I've noticed that he does a lot of "recycling," too (much like Dean Koontz, where it gets downright predictable).
Oddly, I saw the first Salem's Lot movie when I was 10, IIRC. I found it pretty dull and fell asleep during it. That same month I also saw Return to Oz which scared the heck out of me and gave me nightmares of all the heads shrieking at me while the headless witch chased me.
Having had a bad experience reading a short horror story for adults at about that age, I decided to try again with Salem's Lot, since I was curious about the parts I missed having slept through it (and was having nightmares of vampires anyway). The book was much more scary to me. To this days I still have nightmares that I can attribute to that novel.
And the particular odd bit was after I saw the remake of the Salem's Lot (which I liked well enough), I resaw the first version and found it much more interesting now, with moments that were definitely creepy. Out of curiosity I went and rented Return to Oz and found it more silly than scary (even if there was a tiny bit of being creeped out with the headless witch scene again).
One last thing is that I read SK short story The Mist before I read Nightworld. I don't know how much it would've reminded me of FPW novel had I read it first, but when I saw the movie I was definitely thinking of Nightworld. I could see this easily being adapted into a story happening around one of those pits in some small town.