The OT was a great "western in space" type of movies, with charismatic characters and good fun from time to time. The PT is more like watching an old historical movie, with nice costumes, great battles, cool story but (as often with the historical movies) pretty boring to watch from time to time, with one dimensional characters.

I think the well known passion of Lucas for history has killed his skill to simply tell a good story in an entertaining way... But I don't hate the PT. It's just like being forced by a school teacher to watch a movie: first you're happy because it's not as boring as the everyday lesson, but you fall asleep anyway. I feel that the dialogue (specialy in AOTC) increased the feeling of watching a dated movie. I even think that is what Lucas wanted.