My experience with the prequels was similar. When The Phantom Menace, came out, I took Orbert, Jr. to see it in the theater. He was still in grade school. He was blown away. Yeah, it looked cool, and there were light sabers and Force stuff, and that's about all it takes to impress a seven-year-old. I was okay with it, because it was the first new Star Wars in years, and they had a lot of groundwork to lay, so I was okay with the pace and all the other things that are so glaringly obvious now.
We also saw Episode II and Episode III in the theaters (I mention this because we go to the cinema for very, very few movies) and the experience was similar. Kids were fine with it, it was good bonding time, etc. I figured that at some point, they had to start getting better, right? They couldn't get any worse. And II was bad, but I don't know how it compares with I because I'm not a rank-a-holic. I like it or I don't. III was certainly the best.
My kids aren't nearly as picky about films as I am, so they enjoy them. It's all just silly fun space stuff anyway. I'm not actually that picky either, but I recognize that the prequels are pretty weak compared to the original trilogy. But there are some good story elements, just not well executed.