I read the Hobbit when I was 10 and finished the Trilogy when I was 12 then turned and tackled Watership Down. Now I cant wait for the next book by R.A. Salvatore!
I thought that over all the movie did a very good job at capturing the heart of Tolkein.
However!
Aragorn and Arwen were never married nor were they even an "item". It was Eowen, the Shield Maiden, who married Aragorn in the books. He a king and she the last of nobel birth of the wonderful Horse People. This "love interest" just distracted people from the true wonder of the story and caused them to have to drop scenes with Tom Bombadil and the Wright Barrows.
The one thing that struck me in the movie that I missed in the books is how much Sam resembled Tolkein.
They both went into war/hell, watched as those around them were slaughtered and saved lives. They were both gentle simple men who just wanted to live a peaceful life when world events stepped in their way. Then they both came home changed and scarred by their experiences. They even looked alike.
The biography that I read on Tolkein said that he created Middle Earth for the people of Brittan because he wanted them to have a mythology. He studied not the Norse but the Finns, a very small tribe that barely holds on to its traditions today. He was a professor of language and used his skills to invent several languages; Elvish, Dwarvish, and The Language of Mordor. Unlike Klingon, these a fully developed languages with grammar and syntex.
He was by far one of the most amazing men of the 20 Century. He has inspired whole generations to read. Every few years I go back and re-read the books and I always find something new.
Have you ever read the Silmarillion? That is next on my list of books.