I've never had.
Things that mattered
Nothing can equal the joy of reading a good book- not even its visual adaptation as a movie. With the exception of "Gone With the Wind" (which lasted about 5 hrs), no movie that I have seen could bring me the pleasure that its paper and print version brought.
"Angels and Demons" was one such disappointment. But looking at things from a broader perspective, I realized that I must simply convince myself with what was shown. The makers of the film would have met with several restrictions. After all, in today's world where a single word which may not necessarily have been meant to be offensive can easily affect the religious sentiments and result in violent reactions, handling such a tender subject as the pope's liking for the biological science and his not sticking to chastity on the screen would be a serious issue. Theatres might have even refused to screen the film. Also, the palaces in Vatican City could not have been shot easily without several permits and papers involved. There was also the time restriction the makers felt that they must stick to. No longer do people want to watch long movies like "Gone With the Wind".
The reason for the pope's murder will be a puzzle to the viewers who have not read the book. There have been many unnecessary omissions in the storyline like CERN Director's character, Langdon's visit to CERN, the drag theory (that reduces the impact of fall) that I was very much interested in while reading the book and Langdon's use of the theory to save his life shortly before the climax.
Still, I would not consider this film as a waste of two hours. Whatever was shown, was shot and shown well.
Bottomline: Pen is mightier than not only the sword, but also the screen.