Third film:

Pellinor Fields: The dead army do NOT fight and defeat saurons army at Pellinor Fields, they enlist the help of a bunch of slaves and then defeat the army.

Sam: When gollum finds crumbs on sam, and Frodo tells him to go home, Sam does NOT turn back and set off home in the book. this has been made up.

The ending of the book.... hobbits return to the shire to find it being destroyed by orcs. this tells us a lot about the price of war, etc.
The film makes the war out to be happening somewhere else, that they have been defeated on their home ground and everyone can now return home.
The film does not stress like the book how the whole world would be changed if sauron won.

hollywood is so crap, that because it thinks it will lose 20 dollars by putting the real ending in as opposed to the "happy" ending, it opts for the happy option, almost ruining one of the messages of the story. this is why its refreshing to see films like The Usual Suspects and Memento.

Like i said before, Jackson deserves the oscars because nobody else would make this good a job of it. But he is still a nonce and a prat who thinks hes a fan of the books, and he wont be forgiven for messing with the third part like he did.
Not that all three arent exceptional films in their own right. its just frustrating in the highest degree to people who have read the books and know he f***ed it up