More modern copies of the series have the books ordered chronologically, so a lot of people think it is. But The Lion the Witch and the Wardrobe was actually the first book written.
I might be a biased toward the movies since I was raised on them, but LotR is my personal favorite trilogy. I would say the book is even better. There are definitely chapters in there though where the story lags a bit. The Ring Goes South and The Passage of the Marshes would be great examples.
When Tolkien wrote The Lord of the Rings he intended it be just one volume. But because the price of paper was so high in the 50's when it was published, no one would have been able to afford it if it had been one volume. So it was split into three volumes: The Fellowship of the Ring,The Two Towers, and The Return of the King. Some people may argue that this makes it a trilogy not a book, but I stand with the author.
