Normally, DVD featurettes give viewers an insider’s look into a movie. The Ringer is not that kind of DVD.Its featurettes are public service announcements defending the right to make a comedy that doesn’t laugh at the mentally challenged, but laughs with them.In the film, Johnny Knoxville plays a man who pretends to be mentally challenged so he can win prize money at the Special Olympics. But Knoxville and the Farrelley brothers, who are famous for producing comedies like Dumb and Dumber, are careful not to offend.Among the extras are a message from Special Olympics chairman Tim Shriver and a Special Olympics featurette, which includes interviews with Knoxville and the Farrellys, who say making this movie was a rewarding experience.The Farrellys include real-life Special Olympic athletes in the film, and we hear about their positive experiences with Knoxville.The audio commentary from the actors, directors and screenwriter – and six deleted scenes – provide laughs. It’s not what you’d expect from DVD extras, but it hushes any clamor so viewers give the surprisingly charming film a chance.