We all think it strange when we return to places of our childhoods and amuse at how small things are, when at the time they all seemed so gigantic.
Well what about when you see movies that were amazing in your childhood again all these years later...? after watching 'flashdance' for the first time in 20 years I was blown away at how shit it is. When I was a little kid the movie was an amazing tale of a dog loving woman who does man jobs, didn't take anything from a man and overcame everything to follow her dreams and maintain her high morals. Now all I saw was a really bad movie, with bad dialogues and even worse manufactured scenes.
I think its best to keep the memories and not ruin great films by watching them again.