Charlie Chaplin's The Great Dictator, a masterpiece of both comedy and propaganda, is rightly regarded as one of the most important motion pictures ever made. Meaning it's well worth watching in its own right.
If you're put off by all that black and white, though, maybe ease yourself in with some Team Fortress 2 machinima? This clip, by Shwiggan and Gzero, mashes together the film's memorable speech with, well, cartoon characters from Team Fortress 2. It works a lot better than that makes it sound.