Bambi - the first movie I remember seeing in a theater; I was probably 4 or 5. It taught me to love the magic of motion pictures.
Close Encounters of the 3rd Kind - another of the first movies I saw in the theater. This movie taught me to love sci-fi.
Superman: The Movie - another of the first movies I saw in the theater. My sister took me to see it on my 8th birthday, after spending the whole day hanging out with my future brother-in-law. That was one of my best days ever.