Seven Samurai is a very important film to me. I can watch that over and over and catch something new everytime. Kurosawa was a genius and an artist. Film was his canvas, and his imagery were his brushstrokes. I love that film. I could be stranded on a desert island with just a copy of Seven Samurai, and equipment to view it.
Jaws always meant a lot to me too, from a storytelling aspect. That is how a master tells a story.
Close Encounters...I could spend a whole thread on that movie alone...how it is a metaphor for man's relationship with God: The presence of beings from up above inspires people to create something (images of Devil's Tower), and their creations lead them back to the source of their inspiration. That is the nature of art, creation, and how we interact with God, spelled out right there for us, and in such a beautiful way.