I think that's why Episode V is the fan favourite, it has a darker feel, you get the sense that these characters are in real danger, something you never feel in any of the other films and the prequels don't give you any characters to really fall in love with, they are cardboard, two dimensional animatrons who rarely display any emotion that makes you want them to succeed, part of the problem is obviously that we know where the story is going from the begining and so empathising with the main character is out of the question since you know he ends up being one of the galaxy's biggest villians.
Lucas is a great creator on a universal level but his dialogue and failure to give the fans what they want is one of the reasons why there is a love hate thing with the cinema going public but from a purely visual standpoint the films are extreme and without them we probably wouldn't have had any of the big CG and VFX blockbusters for at least another ten years.
I can go on for hours about this, Star Wars really is my passion, I'm so obsessed with it I bought two copies of the Star Wars chronicles books, both the original and prequel books at a cost of £580, so that I could keep one copy of each in pristine condition!
http://www.youtube.com/watch?v=l6io8LefEdI A little something I put together