As for the PT, there are parts of all 3 movies that are great, but the problem is there are parts of all 3 movies that are just plain awful, and really make them all average movies. The PT characters just don't do it for me, as I could care less for Padme & Anakin, and they are the stars of that trilogy. I tried many times for the past year to be a 1-6 SW fan, as I really tried to embrace the PT movies, but the replay value is not the same as the OT movies. There are just too many many problems when watching the PT: Plot Inconsistencies, bad acting, unlovable characters, zero chemistry, etc.
Even though I was there for every PT movie opening weekend, they have not stood the test of time, and that is pretty sad since TPM is only 7 years old. I look at them as EU stuff, something that is interesting to know, but not needed to fullfill the real story of 4-6.
The O-OT story is lean and just one micro story that happens in this huge universe, and that is it's biggest strength. To me is just like reading about World War II and the heroes who saved the world, and yes there is more history before and after, but just like SW, this story is great and can stand on its own.