Jim Sheridan's commentary for In America is definitely one of the best I've ever heard. Like David Fincher in his commentaries, Sheridan's effort here reveals a lot of personal details. He relays his opinions on life, death, art and politics whilst never straying too far from the subject at...
My worst ones are The Matrix (I second the Carrie-Anne Moss comments above) and Bad Boys. Usually Michael Bay is so excitable on his commentary tracks, as his ones for The Rock, Armageddon and Pearl Harbor are very entertaining, but his BB one is incredibly boring. For favourites, I'd go for...