Yeah, the commentary track is one of my favorite DVD features -

What it is is as the movie's playing -- the entire movie -- there's a special audio track that lowers the sound of the film and has Francis sitting there with a mic talking about what's going on at that moment (he's watching it, too). It's usually behind-the-scenes stuff or other interesting trivia.

I love it!

I didn't entirely understand The Wall until I heard the commentary track

JG