Every Halloween, there is lots of talk about horror/slasher scores. I really love the old-skool gothic "romantic" (lower-case "r") scores, mixing a sad, beautiful main theme with "scary" music. Examples would include "The Whip and the Body" by Carlo Rustichelli, James Bernard's Hammer scores, Les Baxter's "House of Usher," and/or anything with Christopher Lee or Vincent Price.
Baxter's House of Usher is definitely a favorite of mine. I picked it up the first time Intrada released it on the strength of the samples alone and have played it relatively frequently year-round ever since. Such atmospheric music. Such a range of moods and emotions. "Enormous" is the word that comes to mind when I think of this score, particularly when compared with the intimacy and claustrophobic feel of the film it accompanies.
I wonder if this 'sound' corresponds to what I generally call "delicious darkness" -- meaning a more romantic, melodic version of horror music (which is really the only horror film music I can stomach to listen to).
Marco Beltrami and Elliot Goldenthal are two composers who excel at this. Chris Young too, once in a while, like HELLRAISER. Daniel Licht used to be pretty good at it back in the day (what happened to him, btw?).
I'd also count Williams' THE FURY and DRACULA, Waxman's BRIDE OF FRANKENSTEIN, Kilar's THE NINTH GATE and DRACULA, Horner's BRAINSTORM...
But again, the sound I have in mind may be different than the one Onyabirri has in mind.