I would usually say the books are better unless they actually have the author of the book help out with the movie, then they have it exactly to the book. Although I do enjoy some of the surprises the movie companies add. Other times, they take out so much it's pitiful. Take the Series of Unfortunate Events movie for example. That was so messed up it was sad.
LotR-Movies
Harry Potter-Books (movies are a disgrace to the books)
Usually I enjoy both, but the book more (I haven't seen DaVinci Code yet, but I'm sure the movie won't be as enjoyable as the book).
Yeah, they took alot of things out of Harry Potter.
Example Sorcerer's Stone: In the Forbidden Forest, Harry went with Hagrid & Hermione before Malfoy. After that, they left out the other 2 centaurs besides Firenze.