I went to a see Last Tango in Paris with a very young friend last year when it played at Vancity Theatre. It was both our first time seeing this very famous movie that everyone seemed to know about. The most famous scene being the butter scene. Anyways, my friend was absolutely appalled and disgusted. She could not understand why this movie would be so famous. I, being the older one (saw more movies/experiences) earnestly attempted to defend "art." I explained that "art's" existence is not to be liked or loved, "art's" job is to invoke emotion - good or bad.
When you see good art (theatre in this case), you instinctively feel something. The Graduate failed to make me feel. I did not empathize with the characters. I cannot exactly identify the reasons why, maybe it's because I had the original images of Dustin Hoffman, Ann Bancroft and Catherine Ross and expected too much (like seeing a movie after reading the book).
"In 1996, The Graduate was selected for preservation in the U.S. National Film Registry as being "culturally, historically, or aesthetically significant". It ranked as the seventh greatest film of all time on AFI's 100 Years... 100 Movies." <http://en.wikipedia.org/wiki/The_Graduate>