Obi Wan says he was trained by Yoda in Empire Strikes back. We then learn this is not the case in the phantom menace, there is some Qui Gon guy who was never mentioned in the original trilogy but was his real master.
Obi Wan claims Anakin was a good friend who was slowly seduced by evil, nowhere shown in the prequels.
The so called great jedi purge is handled in a pathetic and anti climatic way in episode III, this is not Vader betraying the jedi and hunting them down.