Matthew Broderick and Ally Sheedy were the two people that got me interested in computers. This movie made it okay for kids to be dorks, and to wage war with Communists. It may have led to the end of Communism as Gorby knew he couldn't stand a chance against virgins with modems.
Animal House
Belushi was a comic professor in this movie. Without saying more than 25 words, he continues to make people laugh decades after his death.
The Empire Strikes Back
Best of the Star Wars (double) trilogy. Han frozen in carbonite, Billy Dee chillin' in Cloud City, and Luke's Dad chops his hand off.
Leon: The Professional
Natalie Portman's first acting gig, and Gary Oldman is masterful as the crooked cop.
Clerks
Best black and white movie ever made by a fat man in an overcoat for $27,000.00.