Unless you were already into the comics scene, chances are you’d never heard of these so-called Guardians of the Galaxy. Boy, has that changed. The film surprised almost everyone by ruling the late summer box office, thanks to a number of factors: a cast of charming misfits, a wry sense of humor, top-notch special effects, a killer soundtrack, and James Gunn’s steady directorial hand. This is the movie that made Chris Pratt a star and put a dancing baby Groot on everyone’s stocking-stuffer wishlist. With a Tomatometer score of 90 percent and an Audience score of 94 percent, Marvel’s Guardians succeeded in impressing nearly everyone, which isn’t easy to do. If you pick this one up this week, you’ll get a pretty in-depth commentary track featuring James Gunn, a making-of featurette, and deleted and extended scenes, among other things.