I've seen hundreds of movies. Many are great, many are sad, many are powerful. Out of all of the movies I've ever seen in my life, and believe me, that's a lot - the only films that ever really left an impression on me are the following:
Disney's Fantasia (1940)
Qatsi Trilogy: Koyaanisqatsi (1982), Powaqqatsi (1988), Naqoyqatsi (2002)
And while the following isn't really a film, I feel the need to put this here as well:
(Up Series, 1963-present)
Others on my favorite movies list, would be It's A Mad, Mad, Mad, Mad World (1963), The Sandlot (1993), Ron Fricke's films (look him up if you haven't heard of him), Taxi Driver (1976), and recently I saw Five Easy Pieces (1970) that I'm adding to my list. I like existentialism and realism. I was never the drama/horror/romance/fantasy type, personally I always found that kind of stuff to be silly and unrelatable to me.