I agree the Molly Weasley going crazy on Belltrix was the best part of the book, but some of my others include:
1. The AMAZING escape from Xenophilius Lovegood's house (that better make it good in the movie)
2. Bathilda Bagshot cracking open to actually be Nagini
3. MINVERA KICKING SOME SERIOUS ASS!
4. The final walk to the forest with James, Lily, Sirius and Harry
5. Hermione getting tortured ( I couldn't stand it, i had to keep putting the book down cuz i didnt like her getting tortured, ppl say they hate her but i think she was pretty pro skill for the entire book)
6. Everyone showing up to kcik some voldemort ass at the end, but especially the kitchen elves hacking at the shins of death eaters with knives (better be in the movie)