I don't / can't do horror - but LOVE Event Horizon! "Sunshine" has a similar feel though not quite as intense.
Anything with creepy children I just cannot cope with - I made it through The Ring but not The Grudge, and wouldn't touch the original Japanese versions!
For those more inclined to blood-n-guts, try the Korean films Oldboy and Lady Vengeance (there is another in this trilogy which I've not seen and can't remember name of), or Ichi the killer.
Tim Burton is also ace