Lot's of great scary movies out there!
I love the original
Halloween. One of my favorite movies. Sadly the more sequels they made the less scary Michael Meyers became. I don't like explanations on some things evil, it's better to not know. The fear of the unknown makes it much more creepy.
Definitely
The Exorcist as one of the scariest movies. I can remember on the news they were talking about people fainting and one person having a heart attack if I remember correctly.
Jaws probably scared me the most as a child. No rhyme or reason for a shark to attack. It's in it's nature. I swear after I saw this movie I never went any deeper in the Ocean/Gulf further than I can see. This rule still applies today.
The Darkness with Anna Paquin is a favorite. It's atmospheric and interesting plot. I love foreign filmed horror movies.
Tenebrae is a great Italian horror movie.
Alien, the first one, was the best sci-fi horror movie. I also did like
Event Horizon too. Sci-fi and Horror a rare combination of genres that often turn out favorable results.
Sadly now many movies are more about gore and blood and guts than actual plot development and characters. Let's see how many different ways we can kill someone in this flick, que the body count!