Personally I cannot think of a horror movie ever that scared me as an adult. As a child sure. Now, made me jump or grossed-out, sure. But for me, there have been far more games and especially books that are actually scary.
As far as authors go, Lovecraft and Poe were never scary. Good, interesting and enjoyable, yeah, but not scary. Clive Barker and Stephen King have both written quite a few scary books. The Shining, Pet Sematary, It, The Damnation Game, The Hellbound Heart, Christine to name a few.

Mini-review: Just finished reading Ramsey Campbell's "The Nameless". I have mixed feelings about Ramsey Campbell as a horror writer - he's really good at writing horror scenes, but he's not particularly good at writing horror stories. What I mean is, he manages to structure individually creepy images and moments, but has a hard time tying them together with a satisfying plot - it often seems like he doesn't know where he's going so at a certain point he just wraps things up with a Deus Ex Machina. "Hungry moon", which I actually quite liked, was a perfect example of this.

Anyway, so - The Nameless. It's about a woman whose daughter is kidnapped and presumed dead. Years later, she gets a phone call from someone claiming to be her daughter, and starts to uncover evidence of a kidnapper cult who might have stolen her and faked her death. Oh and they worship some ancient evil and want to convert the daughter because of her psychic potential blar de blar. I didn't particularly enjoy The Nameless - the plot was was very by-the-numbers, there wasn't enough supernatural weirdness to keep me interested, and not having any kids myself the kidnapping angle (which is most of the book) didn't really connect with me. Don't give this one to your pregnant wife, though.

Edit: On a related theme, though, I would very much recommend the independent horror film "Absentia". Also about a long-disappeared relative suddenly returning, and dragging some supernatural weirdness back with him, but what made the difference for me here was that I actually found the characters quite likeable and didn't want to see horrible things happen to them. That's an element that a lot of horror ignores or actively sabotages.

Some horror films are simply unbearable to watch. Somebody would have to bribe me with several months worth of rent, or a lego millenium falcon, to get me to sit down and watch 'From Justin to Kelly' ...

I recently saw Paranorman. Thought it was brilliant!
A horror film that I like and for which I find little shared enthusiasm: Lake Placid (ie the first one).
I think that I only really like horror films that do not take themselves extremely seriously: friday the 13th, nightmare on elm st, deep blue sea. Either that or it is the torture element I dislike in films such as Hostel and the Saw series.

Most horror movies and games rely on the sudden "boo!" really. In books you actually have to build some suspension one way or the other.

I really hate all the torture stuff that been coming out during the last half of the 2000's, it looks like it lost its momentum but for a few years it was out of control. Every horror movie had to have someone on a chair having their tongue slowly cut off or trapped in a house or in a room or on a bus and trying to escape for the rest of the movie (most of the times failing). It bored me and grossed me out at the same time, minimal plot and dialogue, almost the same effect as watching a porno (without the benefits a porno comes with).

anything that involve monster especially on excessive numberi found out to gimmicky to creating tense.

I do like horror movies, always have but the stuff coming out the past few year has just been slasher type stuff or things like Paranormal Activity with unseen forces.

I enjoy movies like Evil Dead 1 & 2 (even 3), The Thing, American Werewolf etc

Now though I prefer something that builds a decent setting, I enjoyed the first Silent Hill movie, Midnight Meat Train is also excellent (based on the first story from Clive Barkers Books of Blood and starring Vinnie Jones), Event Horizon is really good as is House on Haunted Hill (original & remake)

I think Saw series and the Hostel movies were the culprits for all the teenage type slasher / gore flicks we have been getting as of late.

Must admit, the remake of Evil Dead was ok, kind of kept the spirit of the originals, just didn't feel right though heading towards the end of the movie. I am surprised that they haven't gone down the remake route for things like Friday 13th & Nightmare on Elm St series, Texas Chainsaw has had 2 remakes in the last 15 year.

Don't like horror of any sort, not in books, movies or games. Really, what is there to like?

I saw <span class="bold">Twixt</span> last week from TV: It was better than I hoped (maybe because I wasn't expecting Val Kilmer to be the main protagonist in any interesting movies anymore; then again it is directed by Coppola, so...), I knew nothing about the movie beforehand. It is not a gruesome splatter, but a psychological thriller.

I think it would make a good game, heck "Twixt" already sounds like a title for some indie puzzle platformer game!

I liked it too, started watching it with low expectations and it turned out really nice and unique.

Those have pretty good movie adaptations (and for me, Hellraiser II is a little better than I).
Misery and it's movie adaptation deserves to be mentioned here too I think.

I love horror movies, I wold like to read novels but I have the attention span of one of jaws's offspring. I collect movies (horror movies take up about 90%). collected video nasties (and love em all), giallo, slashers, low budget (got a bigger appreciation for them, more than the Hollywood shite these days) talking of Hollywood I love the old universal movies from the 30's and 40's, love silent movies (I recommend Haxan to fans of witchcraft movies) I loved it, love the old hammer movies new hammer not so much (didn't rate Woman in Black highly as the original movie was far more atmospheric and creepy and didn't rely on crappy screaming jump scares, also wtf was up with the ending, total BS).
Now onto games loved the resident evil series. silent hill series (first 1 being my favorite horror game of all time) doom series is great as is hexen and painkiller other than them not the greatest FPS fan (much prefer third person games) Phantasmagoria was good need to play the 2nd (more bad than good reviews for the 2nd but I love fmv games and I think I will like it).
I'm a fan of short horror stories and paranormal books aswell (fact or fiction I still find the stories entertaining).
Love tv shows on hauntngs, though ghost hunt shows piss me off a bit.

so yeah im a huge horror fan an always will be

What like when the killer shows up the character should not have run upstairs? :P

On a serious note, Romero kind of pointed to that when he made what I feel is the greatest horror film ever, "Night of the Living Dead". He said his initial concept for the movie, and I'm paraphrasing here, was a group of people faced with a relatively simple and solvable dilemma end up all succumbing to it because they can't think strait, get over their pretty differences, or use any kind of simple logic.