I have mixed feelings about the movie. Its good, but its also bad. I think one reason the movie is so drastically disliked is because it was the first Star Wars film to be released after the OT, so expectations were huge. I think what makes the prequels disliked as a whole is that CGI is used heavely throughout the films, were as in the OT all the sets were real, and looked so great.
But for TPM, I think the "kiddy" tone of the movie hurt it. And what I mean by that is JarJar, and the other goofiness the film had. Some might disagree with me, but that really hurt the appeal of the movie with the adult fans, the ones who saw SW from the beggining. The movie also just didn't have the epicness that the originals had, but like I said, expectaions were very big for this film.
But not all of the film was bad. Of course, it was our first look at the times before the Rebellion. It was very cool to see the Trade Federation and all the Battle Droids and other technology that was introduced. And another big addition, the jedi. This was the first movie that had multiple Jedi in it, rather than just Luke and Obi Wan. The ending Lightsaber battle was definatly a strong point of the film.
So, of course, the prequels can't be as good as the OT, but they showed us everything that had our imaginations going wild when Obi Wan first mentions the Clone Wars back in A New Hope. Phantom wasn't great, and it was a sort of let down, but it gave us SW again, and thats what we wanted.