I have never read any of the books and have always been able to follow the storyline. I know the movies leave out of some of the details in the books, but I don't know the difference. My 11 year old daughter also loved it, but there were a few jumpy moments, so I'm not as sure about the PG rating. However it is a great movie for the family in that it is very entertaining and relatively innocent. I loved it and can't wait for the next movie!!