I've seen most of the film versions of Macbeth, and for me, this is the best. To mention just a few of the most popular: the Orson Welles version is interesting, but very, very dated; the Polanski slow and flawed; the Jason Connery awful. The Ian McKellan/Judi Dench one is an interesting depiction of the Macbeths' relationship, but it's so slow, and because it's a filmed version of a stage performance, the setting gets in the way - it's so dark! Throne of Blood is a masterpiece, but you can't show it to 15 year olds and expect a sensible response!
So, to the Patrick Stewart film. It's dynamic, pacey and engrossing. In fact, in places it's quite scary, which Macbeth ought to be. It's very well realised, and although it's based on a stage performance, the setting is brilliantly exploited. I love the witches, who from the outset are very, very disturbing, and a little bit sexy. Stewart himself is a bit self-indulgent, but he's believable, and that's the main thing that mars all the others mentioned above.
If you're going to buy a dvd of Macbeth, buy this one.