I'll go with my top five, then list any that I feel deserve mention. These five aren't in a particular order, I love them all.
Dances with Wolves
Dragonheart
Gladiator
300
Donnie Darko
All brilliant films, be it for story, content or awesome cinematography. Dances with Wolves is just a beautiful, with great acting and a wonderful story. Dragonheart was my favourite childhood movie, and I still love it for showing Dragon's in a good light. Gladiator is just epic. I studied 300 for a project on my Design Course at Uni, and I must say it's one of the most beautifully shot films I've seen. It's just a perfect film. Donnie Darko is a weird one, but I loves it no the less. I first saw it when I was really ill in bed, and mum rented it for me because her sister had said it was really good. Through my half-asleep, very foggy mind I understood the film perfectly, everything made complete sense. When I watched it when I was better, it confused me to no end. I guess the mind has to be in a dark place to get that movie XD
Films worth mention ~
Jurassic Park
Lord of the Rings trilogy
Princess Mononoke
Watership Down - although it isn't a patch on the book
Numerous Disney and pixar movies
Ice age 1 + 2