For me, and I think I already posted in here like a year ago, but anyway, for me the Hobbit trilogy definitely is one. Because for the books, I always found the Hobbit a lot better and more readable than LotR. Just shorter and more succinct and not nearly so wordy. I always liked Bilbo much better than Frodo and the LotR movies made this even more apparent (they made Frodo look like such a wuss) so I was sure I would like the Hobbit movies much better and Martin Freeman (is that how it's spelled?) really was one of the few parts I liked. And I definitely thought his part could have been better.
I've heard people say a lot of the things they added in the movies was stuff that was in Tolkien's original notes for the Hobbit and that several years after the original release of the Hobbit book, he wanted to release a version with all the left out stuff and someone was like "Hey, not a great idea" and if that's true, then whomever that person was had the right idea. I also kind of hated the elves in the LotR movies. Elrond wasn't nearly as much of a douche in the books. So I go into the first Hobbit movie like "Yeah, dwarves, cool. A cameo of Legolas, but whatever, man, dwarves!" and then? Just two and a half movies of hapless dwarves that would have been fun if their distinct personalities came with an ounce of competance being saved by the blond ninja of Mirkwood and the chick he's into. I say two and a half because the dwarves were almost getting it together in the first one. But it still had some elves pissing me off. Like Elrond being all like "Gandalf, bad wizard. You're grounded." Bitch, please. Gandalf the Grey has to ask your pointy eared ass for permission?
Sorry, that rant kind of got away from me.