1. Raiders of the Lost Ark -- Not necesarily the best film by Spielberg, but the first film I ever saw that made me truly love movies. I could just as easily switch this out with Jaws.
2. The Godfather Part II -- The most exciting, non-action film ever made. Pacino and De Niro rock the house here. The film gets deeper, darker and better as it goes. And that ending ...
3. The Empire Strikes Back -- The best of the Star Wars movies. Not just because it's darker, but because it's more textured and layered than any of the other films in the series. Hopefully this is the blueprint Abrams uses on VII.
4. The Shawshank Redemption -- An amazing film that, while a little long, astounds with one of the -- if not THE -- greatest endings of all time.
5. Saving Private Ryan -- Spielberg's masterpiece. Seriously. This was the last film he directed that truly changed the world of cinema. Without Saving Private Ryan there's no Black Hawk Down, Call of Duty video games, WWII monuments, Band of Brothers, The Pacific. Spielberg's made great films since then -- Minority Report, AI, Catch Me If You Can, Lincoln -- but none were game changers.
6. It's a Wonderful Life -- I have to include this because, dammit, I watch it every single year without question. Jimmy Stewart is fantastic, but it's the overall notion that we take the little things in life for granted that really sticks.
7. When Harry Met Sally ... -- The best rom com ever made. Period.
8. Heat -- Michael Mann's masterpiece. A brilliant crime caper with solid action, terrific performances, and a powerful ending.
9. Aliens -- James Cameron's masterpiece. I loved True Lies, Titanic, T2, and even Avatar, but of all his films, this is the one I watch the most.
10. Jurassic Park -- This should be higher, especially after the rerelease drove me to spend 30 additional bucks on a movie I've seen over 100 times by now, but which film would it replace? Another Spielberg rollercoaster that ultimately changed the cinematic landscape. As a kid, this blew me away.
Others: The Dark Knight, Lethal Weapon, Die Hard, Rushmore, Alien, Return of the King, Rear Window, Back to the Future, The Departed, Life of Pi, To Kill a Mockingbird, The Omen, Unforgiven, The Sting, Heat, No Country for Old Men, Finding Nemo, Glory.