Well you have to remember that books are not the films, and vice-a-versa. You have to really remove yourself from that way of thinking, or you will never enjoy the translation of the books. It is the same for LOTR, some people just couldn't get passed the way PJ translated the films... the things that were left or changed or added. And if you think like that you really are missing a lot of good things.
Having said that, as a non reader of the Potter books, i found that POA was the ONLY film in the series that was watchable. I understand that the first two stayed closer to the books while the last one strayed (though it was longer, yes?). BUT, the last one was the only one that was well made. The film was handled perfectly, regardless of what was left out. I actually own POA and am not a real "fan" of Potter.
But hey, just my 2cents