I would have made it longer. I suspect the DVD will have some additional scenes.
I'm used to Masterpiece Theater adaptations of novels, which can easily go to six hours.
In the books, Harry goes to school, and much of the charm of the books is in the descriptions -- not of the content of witchcraft -- but of the personalities and methods of teachers. This is what's so fascinating to kids of all ages.
I just don't know how that could sell. In any book translated to the screen, you've got to lose something.