Too bad the title is misleading...
I enjoyed this movie a lot, but I was expecting it to be a combination of both books based on the characters. I suppose that would be difficult to do, and Huckleberry Finn has never had a successful film adaptation, but it's still a great book, in my opinion a much better novel than Tom Sawyer.
Unfortunately, I doubt that they'll ever do a good adaptation of Huckleberry Finn, because it is always considered too offensive and mature to turn into a kids' movie, but since it's based on kids, Hollywood expects adults wouldn't watch it.
At least I would give it a chance.