I don't know why every one hates the prequel trilogy i mean the story is amazing behind it and we got to see the rise of Darth Vader. Yes the originals are classics but people should appreciate the prequel trilogy more.
Admittedly, the core stories behind the prequels are pretty good, but remember that a good story by itself does not a good movie make. While the concept for the PT was decent enough, the execution was terrible. Most of the main characters were obnoxious or unlikeable, the dialogue was atrocious, what "humor" there was just came across as juvenile and dorky, most of the acting was incredibly wooden, many visual effects (particularly CG characters) were so over-the-top that they destroyed suspension of disbelief, and the editing left much to be desired. Take all of those factors together, and you've got yourself a pretty good recipe to utterly destroy an otherwise potential-filled film project.
Compare that to the OT. Luke, Han and Leia are all very likeable, while Anakin is leery, creepy, obnoxious, arrogant, self-absorbed & whiny, Padme comes across as a shrill activist (and somehow manages to be even preachier than Jean-Luc Picard), and Jar-Jar is just plan irritating. A film is primarily character-driven, and if most of your main characters have nothing at all to recommend them...well, you get the idea. Dialogue? To be fair, the OT has never been touted as a pinnacle of rhetorical excellence, but when you compare its dialogue to that of the PT it comes off sounding like Shakespeare. The OT had plenty of humor, most of which was personality-driven and genuinely funny. The PT relied on silly saturday-morning-cartoon dialogue, terrible puns, and poop & fart jokes to carry the comedic element. Does the OT have better acting than the PT? I've never met anyone who would argue otherwise. Compare the worst acting in the OT (probably the Ewok village conversation between Luke and Leia in ROTJ) to, say, the "Are you an angel?" interaction in TPM, or the fireplace scene in AOTC. You get the idea. In the OT, the visual effects were very convincing and believable (and managed to take backseat to the story, thankfully.) On the other hand, I simply cannot imagine a willowy seven-foot-tall eighty-pound thin-as-a-toothpick creature existing on a stormy planet and not being blown away by the wind. Finally, consider the editing. The OT had very tight, fast-paced editing which flowed beautifully. The PT dwells on scenes waaay too long (which destroys pacing), and overexplains things that should be obvious to the audience almost as the rule, not the exception.
Anyway, hope that answers your question. It's not meant to be derogatory; simply to explain why I (and presumably quite a few others) find the PT to be so incredibly inferior to the OT, and therefore don't really appreciate it very much.
(By the way, as kewl as the notion of seeing the rise of Vader is, it's kinda rendered totally unkewl when he's ten times more likeable as an evil villain than he is as a "good guy.") ;-)