I enjoyed Vince Vaughn's Wild West Comedy Show. may provide a strong contender for his child acting typecast. The film shows clips from an Afterschool Special on which Vaughn and Billingsly became lifelong friends.
DVD Review: Wild West Comedy Show
The four spots on the comics have interviews and road footage which you can probably skip. You'll want to see their extra standup routines though. They're funny beause they're true.
Some musical bits are iffy. A Grease number is basically the one joke of Justin Long doing drag to sing the Sandy part. You do hear them sing a few versus. There's also Vince Vaughn singing "Sweet Caroline," which I think is the worst karaoke song ever. It's too accessible, too many people do it and they just scream. So the experience of enjoying Vaughn's interpretation was soiled by my own real life experiences.
Things like the "Dinner for Two" and "Six Degrees" are not extras at all. They are behind the scenes discussions, either of prepping the Jon Favreau sketch, or even just talking about how everyone met on the set of the Afterschool special. These may be valid but they belong in a different section than Bonus Footage.
There are some good extras worth having, and I like the guys so I may at some point explore all the behind the scenes stuff. Just know that when you're looking for deleted scenes, you might want to scan ahead.