Thanks to my daughter, she turned me on to read the full saga... I was a bit of a sceptic at first, but once I finished the first book, I couldn't stop... "It's crack on paper!"
This movie of course is not as detailed as the book, but it sure helped with my own movie in my head... I can agree with some of the viewers that reading the book is the only way you can appreciate some of the "inside" jokes in the movie...
It's really up to you if you want to see the movie first, then read the book or vice versa...