Aliens
I love science fiction and I definitely love stories set in a dystopian future. With that being said, I've never been able to muster the courage to watch Alien or Aliens because it used to freak me out so much as a kid. Back when I lived at Alton Towers we had to take out our trash in a garbage chute, which required me to walk around the corner and into a room. One day, after watching bits of Alien I kept imagining the aliens crawling up the chute and ready to pounce on my face and come out from my belly. I never took out the trash again.
I also never watched any of the Alien series despite the first two being directed by Ridley Scott (!) and James Cameron (!!) respectively. So! Today I figured I'd go out and buy one of them and ended up with Aliens (the second one directed by James Cameron) because I need to overcome this fear. I just hope this finishes before the sun goes down.
Edit: This movie was friggin' awesome! Ripley duct tapes a machine gun/grenade launcher to a flame thrower. Damn! And Bill Paxton is the greatest. Time to watch the first one!