The Ringer

Johnny Knoxville's Steve pretends to be a retard named Jeffie so he can compete in the Special Olympics and win money in The Ringer. Directed by Barry W. Blaustein (who's written many Eddie Murphy movies like Coming to America, Boomerang and The Nutty Professor) and written by Ricky Blitt (Family Guy), the story is not stupid or tasteless as one would expect. It's silly but is also funny, and despite a very weak beginning, it gets very good once Knoxville gets to the pre-Olympic competitions and is joined by the other mentally challenged athletes. Sorry about the retard remark before, btw.

But why does he go to the Olympics? Because he needs to raise money to pay for surgery for a friend, who is not actually a friend but an old guy he should've fired at work but instead decided to hire as a lawn mower and after an accident the guy ended up with three fingers chopped off his hand. And it's a huge hospital bill because apparently in this movie's time there are none of those organizations that pay the bills for you if you can't. But oh well, I guess it's necessary for the story to work. There's another reason too, as Steve's uncle Gary (played by a what-the-hell-are-you-doing-taking-these-roles Brian Cox) needs money to pay the mobs for his gambling.
At the Olympics, Jeffie must compete against Jimmy (played by Leonard Flowers), the mentally challenged superstar who's won the games 6 times in a row. There's also Katherine Heigl's Lynn, an instructor at the Olympics who helps Jeffie along the way while he falls in love with her.

There's been some controversy lately about this movie, as South Park creators Matt Stone and Trey Parker are saying the movie rips off an episode of their series they released in early 2004, but the movie's producers say the script was written before that. Lawsuits may be filed, but whatever the outcome, the South Park episode was funny, and movie is funny too. Supported (mostly) by a cast of real life mentally challenged actors, The Ringer shows its heart, and it's surprisingly respectful of the characters we all thought it would be making fun of.