the age of Frodo was fine. the whole Arwen thing was unnecessary. the other minor differences didn't really matter
Differences between books and movies

I agree about Arwen
Also the whole thing about Aragorn not wanting to be king in the movie. He wanted to in the book

What do you think about Bilbo’s appearance in the LOTR movies? The book says that the called him “well-preserved, but unchanged would have been nearer to the mark”
The movies have a lot of differences from the books. But which of these changes were necessary, helpful, and harmful? Discuss!