ok,ok, so now I've vented my spleen, maybe it's time I got a bit more constructive.
I think the basic story and plot arc of those movies was reasonably ok, but like Knightmessenger said, could have done with a lot more tweaking. Get rid of the dumb crap for a start and it would instantly be more watchable.
Like Sluggo said, the Jedi should have been more kick ass and proactive and kick a few heads instead of being totally in the dark and reactive to every situation. Give the Jedi a heart of gold, but throw in a bit of 'Sam Spade' grit as well. It worked for the Han Solo character and I think it would make the Jedi characters more 3-dimensional.
I would also like to have seen the young Anikin use the force and cheat to win the pod race. This would have given us an inkling into a flaw in his character right from the start. That flaw could grow as he got older and ultimately be exploited by Palpatine. I just didn't buy the utterly nicey nicey Anikin character being manipulated so easily and suddenly turning into the complete b*stard that he became in the later movies.
... just another 2c.