What Am I Missing?

I just finished watching this movie, on the recommendation of my professor, and I would like my two hours back.

At the risk of sounding pretentious, I have a reasonably sophisticated taste in movies, at least compared to my peers. This film is obviously the 'sophisticated' sort but it seemed completely pointless to me. An old gay guy follows a young boy around Venice for two hours and then drops dead? What am I supposed to learn from his experience? Would I appreciate the movie more had I read the book beforehand?

Regards,
Mr. B