The prequels were perhaps less entertaining than the original three (although I really feel this depends on one's age at first viewing), but when considered carefully they rhymed beautifully, and said something deep about contemporary society as well. It helps to consider the fact that the "good guys" in the prequels are the "bad guys" in IV-VI. Then compare Luke to Anakin. Lucas tried something audacious, and it worked magnificently, and maybe a dozen people understood it. Then he could sell the whole mess to Disney with a clear conscience.

http://www.starwarsringtheory.com/

I don't hate II and III, they're ok. The first prequel was terrible though. I recently watched the movies in Machete order with my kids and it was pretty good. I probably won't do it again but I don't regret it. The most recent Disney ones have been utterly dire. I skipped the last one completely and nothing Ive heard about it inspires me to give it a chance.