Gilgamesh, glad you are liking the movies! I think this is a really great idea, and hope you or someone else picks up the idea. (I like say, the modern Doctor Who's, Torchwood (must watch most of Dr. Who first), The Scrapped Princess, Full Metal Alchemist, etc.)
It's interesting reading peoples responses. One of the things I loved about the 5th book was all the dark political stuff - but I'm older than most people here, and lived through a bunch of clear dark deception - that I think is well captured in the books (and somewhat the movies). Where you aren't really sure who the good guys are, who to trust, what the truth is - just like real life.
Separate thought - I think the problem with Goblet of Fire is that the book is so good, that the movie is a let down if you have read it. But not as much of a let down if you haven't.
I think the Harry Potter series will be held in regard like Lord of the Rings and other such books.
Anyway, enjoy the last one!