Why do I think that the PT is shite? Where to begin? I'm going to challenge myself by not just pointing you to Red Letter Media, and instead voice my grievances myself.
Lets start with Episode One. The low-hanging friut are Anakin and Jar-Jar. But there is something deeper running here. I honestly couldn't give a shit about the actual story. A bunch of merchants who sound like Fu-Manchu and are totally ineffectual blockade then invade a planet that I have no reason to care about. There is no sense that anyone is under any stress except for stilted dialoge saying "WAR IS BAD" and "SLAVERY IS BAD". Movies are a visual medium. These things should be shown, not just told in cold dialoge. Everyone who isn't irritating talks in a stale monotone, as if showing emotion isn't allowed. And there is no one who is central to the plot. For a movie based on a series that is cited by Joseph Campell as a prime example of "The Hero Arc" this is a serious offense. And Darth Maul is the biggest waste of a villian, given the amount of fucking hype he received in the lead-up to the film. By the way, Duel of the Fates wasn't interesting because it had no consequence to the rest of the climax. It was a lightsaber fight for the sake of a lightsaber fight.
Episode Two. George Lucas abandons using real sets for CGI, and boy, does it show. Anakin has aged 10 years through perhaps the most important years of his life as far as character development go, and we are told nothing about it. Instead, we get a trilogy that's essentially a character study, but flat out fails to show how a character develops. Anakin fails to evolve at all in this film. Okay, he gets married, but he's still the same character. He's ready to fall face first into Natalie's breasts at the start of the film, and he's still that way at the end. The plot itself is nonsensical. If you asked what the characters accomplish in this film, the answer is essentially nothing. A bunch of events happen to them, and they flat out declare that nothing was accomplished. There are stretches of the film that I can't watch, or cause me to burst out laughing when I'm well aware Lucas was not aiming for that reaction. The love story is dead on arrival, somehow Out-Twilighting Twilight before Twilight was even written. And the relationship between Anakin and Obi-wan was painful to watch. Aren't these two supposed to be friends? Making Anakin into an unlikable twat is pretty damning if the central story you're trying to tell is how he falls from grace. Because if he was a dickhead to begin with, then absolutely no pathos is generated when he becomes a different kind of dickhead.
Episode Three. The most glaring flaw with this movie (and one that I noticed before Mr. Plinkett pointed it out) is that everyone is a total moron. Anakin, Obi wan, the Jedi, the bad guys. The attempt at political relevance is so embarrasing that it would make Seth McFarlane blush. Grievous is just another Villain of the Week. The mood whips wildly around going from fun adventure to mafia-style executions and child murder. Anakin's fall is totally unconvincing. George tries going for a Grecen style tragedy but instead everything is so contrived. The utter lack of chemistry between Hayden and Natilie makes any notion that Anakin's love for Padme is the cause of his fall utterly laughable. And then, he runs straight from willing to do anything to protect Padme to killing her at the first sign she might not approve of what he's done. The whole segment on Kashyyk is needless padding. There is no reason for it to be there. Padme is reduced to being a prop. None of the actors ever conveyed a sense of urgency. "The Chancellor is a Sith? We must hurry." says the man not moving faster then a brisk pace. And like the second movie, there is no sense that anything was accomplished. It speaks volumes that when Anakin fell to the Dark Side, I didn't felt pity, but relief that we finally got past that plot point. I've heard the argument that Palpatine is so powerful that he fills all the plot holes. There is a name for this plot device: "A Wizard did it." Not only is it incredibly lazy, but is discredited because in the last movie, Palpatine loses. If we follow Occam's Razor, then the simpler answer is that everyone in this film is criminally stupid.
I know what some of you are saying: that the Original Trilogy was jsut as dumb. And that's just bullshit. We're talking about a collection of movies cited by literary scholars as the ur-example of ageless themes in story telling. I'm more than willing to put up with its flickering lightsabers, hand puppets, and ewoks, because the story it tells is so compelling that it grabs my attention and refuses to let go. And if you're honestly just watching these movies for the special effects, then there are much better movies and directors that can satisfy your need for that. I'll admit, I just want to watch action and to hell with the plot. In which case I watch Avatar, or Transformers, or Star Trek, or Tron: Legacy. In these movies at least the actors show interest in what is going on around them.