Chamber of Secrets has the most deleted scenes available of the 4 and I heard there was a lot more filmed with that too. One of the actor interview features has a behind the scenes shot of Harry saying "and the crowing of the Rooster can kill it." This is not in a deleted scene and was cut from when Harry and Ron realize from the page in Hermione's hand just what lies in the chamber.
Azkeban I don't think had a lot of extra material but I still think the movie moved way too fast at the end. Why weren't the great quotes from Sirius "Harry you are truely your father's son" and Dumbledore to Harry "I believe you did see your father last night. You discovered him inside yourself. Prongs rode again" in the movie.
And where the hell was the menu for the deleted scenes in Goblet, it just played them all in sequence? I did hear the graveyard scene was cut from 20 minutes.