If you're looking for a fun (and somewhat comedic) science fiction movie, Back to the Future more than fits the bill. With a great, over the top comedic performance from Christopher Lloyd and more pop culture references than you can shake a stick at, this has to be one of the more enjoyable SciFi/Comedy movies ever made.

Take your stinking paws off me, you damned dirty ape! This is one of the most famous lines in Science Fiction history, and it's also the first words ever spoken by humans to apes in Planet of the Apes.