IT... Damn why did I have to remind myself of that again? Evil evil film... The first one, with the children is the best. For me arguably the worst scene is when theay are adults - the old lady tea drinking scene. It makes my neck hair rise just thinking of it.
If you are into horror then you have probably already watched the great classics : Alien, Aliens, Predator, Predator 2(i liked it), Silence of the lambs etc.
House on haunted hill freaked me out.
Relic is another lesser known and underrated gem. Oh and some x-files episodes have strong horror elements eg the one with the glowing spiders and squeeze - the guy that munches livers...
The Thing is legendary...
Never ever ever watch Hostel. Seriously stay away from it. The horror is too real and sickening.

My favorite comedy horror film is definitely Lake Placid.
The absolute worst horror film however is 'Liefling'. I would rather watch 'From Justin to Kelly' 3 times concurrently...

I love horror movies. Event Horizon, In the Mouth of Madness, Santa Sangre, Wild Zero, Who Can Kill a Child?, The Toolbox Murders (1978), etc are all great. Recently the Mother's Day and Evil Dead remakes weren't bad either.

Here are some recommendations (available on Netflix in US) people might not have seen:
Dead End - a family picks up a hitchhiker... sounds cliche but still great supernatural horror fun.
The Asphyx - 1970s British film about scientists trying to capture the essence of death, that is better than it sounds.
Salvage (2008) - about a town under siege by supernatural and military forces.
Fascination - a film about a thief in 1916 who stumble on two women in a mysterious house.
Cropsey - a documentary that looks at a horror urban legend in New York.
Vamp - a strip club vampire chase movie.
The Theatre Bizzare - an anthology film.I like the Hellraiser series, after part III they become less focused but more abstract and dreamy (nightmarish?)

It has been too long now since I watched "The Exorcist," "The Omen," and "The Shining." I should watch these again soon and at night of course, alone.

Has anything been released in recent years that can compare to these for horror, maybe something I could rent from iTunes?

I love watching horror films any time of the year. I live about a half-hour from one of the last drive-in movie theaters; I got to see a double bill of Phantasm and Evil Dead II there during August a few years back. That was pretty cool!

I love horror movies all the time. :) It can be somewhat difficult to find, but Noroi is a fantastic film. It's not been released in America, I first watched a download before I decided I loved it so much I got a copy from Hong Kong. It's a Japanese found footage style horror film, with several story threads that all come together brilliantly.

Horror movies are my favorite kind of move done right, but I've run into the same problem as you. Went through my Netflix account and probably watched any half-way good one twice.

Some recent atmospheric/tense movies you might enjoy are The Orphanage, The Innkeepers, or Session 9. The Orphanage is one of my favorite modern horror films (it's in Spanish). It's older but if you've never seen The Changeling then go watch it now.

You my friend are very wise in the ways of horror. Same approximate time and even more overlooked that the Changeling is The Sentinel. Either way they are both classics.

SHIT! Now I'm going to be thinking of that fucking ball rolling down the stairs all night which means no sleep for me.

You mean this? http://www.imdb.com/title/tt0099864/ ? (has 2 parts).

<shudder> yep thats the one. The first part follow the story when the protagonists encounter it as kids, and the second part when they are adults and they suspect that it has returned. The first part is considered to be the best. Thankfully it is 12 hours till sleepy time so i have plenty of time to forget about it till then...

This. I watched this again two days ago, and it's still absolutely fantastic. Scared the living shit out of my niece too ;-)

I enjoy watching horror movies anytime, anywhere. The problem is, it's near to impossible to find a GOOD horror movie in a cinema nowadays.

So I stick with classics.

Evil Dead reboot was kinda good, though.