Let me start by saying that I have never been a fan of the HP movie series. Some franchises just don't translate well into film - like G.I. Joe. Who's idea was it to make that into a live action movie? HP has so much fanciful paraphernalia that when it all comes together on screen it seems a bit... weird. Hokey. And I LOVE the books.
There is too much depth, too much emotion in the books that is missing from the movies. Not to mention certain characters and plotlines: Dumbledore has never been portrayed right, and WHY did they keep that redheaded girl as Ginny Weasley even when it was clear that she was terrible for the part? Ginny is supposed to be cute, funny, smart, and brave. The one in the movie was just... there. THIS girl on the left is closer to the book's portrayal of Ginny, as opposed to the chick on the right. I found this on some harry potter website. As you can see, the bio is pretty exhaustive.
But besides the fact that my favorite heroine of the HP series was done serious injustice throughout all the movies, HP7:2 just didn't do it for me. It missed a lot of emotional goldmines, brushed over the actual Battle of Hogwarts and its impact, and added scenes that didn't really add any pazazz. It was pretty much action porn (all action, no substance) which is regrettable since the conclusion of the book is so epic.
Anyhow, if you haven't read the book, go do so. The books > the movies.
Oh and Wizards > Muggles. period. Lumos!