1. The Patriot (2000)
Hot off the heels of Braveheart in the once-thriving "Mel Gibson slaughters a bunch of cartoonishly-evil British dudes" genre, 2000's The Patriot starts out as an interesting portrait of a farmer who just wants to settle down after living through the atrocities of the French and Indian War, then after about twenty minutes, it just goes full-on "f*ck it" and it turns into two hours of Mel Gibson butchering dudes with a tomahawk.
Plus! If you thought the Brits in Braveheart were hilarious caricatures of mustache-twirling action-movie-villains (did you know there's no historical account of Longshanks ever declaring 'Prima Nocte'?), then buckle up for the bad guy in The Patriot, who not only shoots Mel Gibson's ten-year-old son, but also BURNS A CHURCH FULL OF INNOCENT PEOPLE ALIVE FOR NO REASON (despite the fact that British generals essentially lost the Revolutionary War because they were too gentlemanly.)
Spend your 20 minutes more wisely and just watch Mel Gibson's Mr. Smith Goes To Washington remake.