They are worth getting, but they don't!
It would be easier to pack all of LotR into six films, but some bit would drag, so quite a bit is glossed over. I must have read the books twenty times, but I always skip the songs! You have to accept that a film has different pacing requirements to a book, and that there will be plot changes. Don't be put off, the films are a marvellous side dish to the books! I always (re)watch the extended editions in preference to the cinema releases, at least once every two or three years...