Honestly, I don't think there are many movies that are really about St. Patrick's Day. But at least there are a few movies about leprechauns. And any number of movies you might want to watch on St. Patrick's Day just because they're Irish, or about Irish people, or whatever. I dunno. Look, if you're like me and don't like going out, you need to watch something while you're sitting at home drinking your Guinness, so here are a few suggestions. (There are surely other movies I've reviewed on my site, which are set in Ireland or are about Irish-American characters, which I'm not listing here just because... well, just because.)

The Boondock Saints
The Commitments
Darby O'Gill and the Little People
Far and Away
Leprechaun
The Luck of the Irish (TV movie)
The Magical Legend of the Leprechauns (TV miniseries)
The Secret of Kells (animated)