I really enjoyed the movie version of Dan Brown's novel (I enjoyed the novel, too). Considering that we all know where the story is going and how it ends, we're really just going to the cinema to see all the paintings and riddles and religious sites from the novel (like the Louvre and Rosslyn) up on the big screen.
And I thought Ron Howard and his team made it nice and big , momentous, an event, with deep music and cool crane shots. The book has a big conspiracy theory in it, and the movie felt worthy of that. (If you're interested in the Jesus-and-Mary-Magdalene-as-man-and-wife theory, have a read of The Holy Blood and the Holy Grail , the main source for Da Vinci , it's incredible, a real page-turner, arguably even better than Brown's novel for sheer readability.)
If I had any major criticism of the movie version, it would be that I wanted to see more interpretations of the hidden meanings in Renaissance artwork-like where one figure in a painting slices another's throat. But in a movie, you have to cut something, otherwise you end up with a ten-hour film, and I accepted that. Very enjoyable.