The below list is not in a particular order but I do highly recommend the first two on the list to horror geeks.
1. Shutter (2004) (Thai Supernatural Horror). There is also an American remake but I would advise watching the Thai version first.
"A young photographer Thun and his girlfriend Jane discover mysterious shadows in their photographs after fleeing the scene of an accident. As they investigate the phenomenon, they find other photographs contain similar supernatural images, that Thun's best friends are being haunted as well, and Jane discovers that her boyfriend has not told her everything. It soon becomes clear that you can not escape your past". - IMDb
This is without a doubt one of the scariest films I have seen, and I have watched a lot of horror films. Not only is it scary, jumpy, but it has mystery to it too, and a great ending. A top notch horror film.
2. A Tale of Two Sisters (2003) (Korean Supernatural Horror). This what the American horror The Uninvited is based upon, I haven't seen the later but I am going to assume that the original is better - they usually are. Another Asian horror film gem.
"Two sisters who, after spending time in a mental institution, return to the home of their father and cruel stepmother. Once there, in addition to dealing with their stepmother's obsessive and unbalanced ways, an interfering ghost also affects their recovery". - IMDb
This one takes quite a lot of thinking and you need to pay attention to it to understand what is happening, but it an excellent film once you have your head around it. I advise you watch it with someone so you can discuss what is happening - I advise this for most Asian horror films.
3. The Amityville Horror (1979) (American Supernatural Horror). Before I discovered Shutter this was my 'most scary' horror film. Like the last two films mentioned the original is far better than the remake, if you want a swatch at Ryan Reynolds abs then watch the 2005 remake - but I find the original so much more eerie. This film will set you on edge and having you flinching at every little noise you hear.
"Based on a true story that was claimed by writer Jay Anson, The Amityville Horror is about a large house on the coast of Long Island where newly weds George and Kathy Lutz and their three children move into the house that they hope will be their dream house but it ends up in terror". IMDb
This film scared me for a long time and the background story behind the Amityville case is also really quite interesting.
4. Ringu (1998) (Japanese Supernatural Horror). Only watch the Japanese series of Ring films, if you watched the American versions and found them really good then this is probably the wrong post for you.
"Reiko Asakawa is researching into a 'Cursed Video' interviewing teenagers about it. When her niece Tomoko dies of 'sudden heart failure' with an unnaturally horrified expression on her face, Reiko investigates. Shes finds out that some of Tomoko's friends, who had been on a holiday with Tomoko the week before, had died on exactly the same night at the exact same time in the exact same way". IMDb
5. The Texas Chainsaw Massacre (1974) (American Slasher Film). This is very possibly the first horror film I ever bought. It was that or Friday the 13th (another one to take note of). I just absolutely love the story of Texas Chainsaw Massacre - the crazy dysfunctional family and the psychology behind leather-face (based on serial killer Ed Gein). Taking into account the small budget this film had, it is a great horror. I sometimes feel that modern special effects make films less scary. There is a great coldness to this film and the silence in parts really does create a horrible atmosphere both in the film and around you - grab a blanket.
"Five friends visiting their grandpa's old house are hunted down and terrorized by a chainsaw wielding killer and his family of grave-robbing cannibals".
I also enjoy the follow up to this film also by Tobe Hooper (not to be mistaken for the remakes, gosh I seem to really hate remakes). IMDb
6. The Shining (1980) (American Supernatural Horror). Without a doubt this is a classic. Based on the Stephen King novel, it is simply a great tale of mystery, psychology and supernatural activity. It is a film I have yet to proper work out, but one day I will sit and tear it apart, perhaps with a glass of red-rum.
"A family heads to an isolated hotel for the winter where an evil and spiritual presence influences the father into violence, while his psychic son sees horrific forebodings from the past and of the future". IMDb
It is a Stanley Kubrick film and it stars Jack Nicholson - need I encourage you further?
At the moment I have no opinion on the prequel to The Shining that is currently in the works. I don't know whether it is a good idea or a disastrous one - I suppose time will tell. I do have a lot of opinions of the remaking of American Psycho though - again blooming remakes!
Stay tuned for part two and my post for halloween films for those that do not like horror.