In general I prefer slow, creeping horror to "gotcha" scare tactics.
I find that I've had better luck with Japanese horror films than others for this kind of horror.
was good. Hollywood's remake was significantly less so.
was good, and plays to a particular paranoia of mine, i.e. things that aren't alive and should not be moving around coming to life and moving around with murderous intent, inexorably and inevitably.
Much as I love a lot of things about Japan, sometimes I get really skeezed out by the things that have been produced by Japanese media.
Also, zombie movies (yes I'm serious):
Return of the Living Dead
is comedic, but also horrific in its way.
is a movie out of Hong Kong, also comedic and horrifying.
I consider them horrifying in a similar vein to fridge logic: not so much at the time, but you really get it after it stews for a bit in the back of your mind. For me the horror is seeing what happens to people trying to survive, but ending up losing their humanity anyway. Hope is a delusion, but without it, there's only death to look forward to. And you can keep fighting and running but eventually you'll beg
someone to kill you before those things tear you up and/or make you into their latest recruit. Also tip of the hat to The Walking Dead
for similar reasons.