My problem with the prequels is, essentially, the blockbuster representation of everything wrong with Star Wars in general: Lucas changing/adding scenes, the poor editorial oversight of the Expanded Universe to the point where entire series have had to be retconned, all of that.
And that's a big problem with me because I'm obsessed with canon. When I get into something, I want to get into all of it. This is why I can't get into most comics: no consistent canon. They keep bloody changing things. This is why, after reading over 100 Dragonlance books, I had to stop reading them; inconsistent canon. This is why I'm reading the Discworld books in publication order; full understanding of preexisting canon.
Sure, I can enjoy a one-off story, but it's so much better if I know everything that's going on and have a firm grasp of the setting. Destroy the setting by mangling the canon and I'm having a lot less fun. This is part of what makes Song of Ice and Fire so much fun to read: a minor mystery in the first book that is speculatively solved immediately isn't fully resolved until the third book, bringing current events into sharper focus.
That being said, while I despise the prequels for their failed realization of a childhood dream, they were merely a representation of the cancer that had been eating away at Star Wars canon for years, and I had already moved on to far, far greener pastures. I am not a bile-spewing Star Wars fanboy because it's just not worth it; there are far better series out there, and my time is better spent enjoying them.
So, to every bile-spewing Star Wars fanboy out there, go read:
The Kingkiller Chronicle by Patrick Rothfuss
The Song of Ice and Fire by George R. R. Martin
The Dresden Files by Jim Butcher
Honor Harrington by David Weber
The Death Gate Cycle by Margaret Weis and Tracy Hickman
Discworld by Terry Pratchett
And everything written by:
Brandon Sanderson
Neil Gaiman
Michael Crichton
Isaac Asimov