The movie of Angels & Demons was an enjoyable adventure. It was fairly close to the book, although probably not as close as it could have been. Nevertheless, I thought it worked well.
I liked the book better than the Da Vinci Code, but I'm not sure about a movie comparison. I still like the plot better, but the Da Vinci Code movie has the distinction of including one of my favourite movie scenes ever. (The final scene, when Robert Langdon follows the rose line through Paris to arrive at the Louvre and kneels above the sarcophagus of Mary Magdalene.)
Upon reflection, I think the movie of Angels & Demons lacked the character development of the Da Vinci Code. So, although the latter movie had more plot holes, it had more complex characterisation. Perhaps this is why I felt a little underwhelmed by Angels & Demons, despite having enjoyed the book better.