There are great aspects of the PT and there are horrible aspects of the PT. I hate to sound like a "PT Hater Broken Record" but there were plenty of laughs in the OT and none of it was in-your-face silly slapstick. It was things that happened ORGANICALLY to the story that allowed for a laugh.
The best example I can think of off the top of my head is when Han, Leia, Chewie and C-3PO are running through Echo Base to evade the incoming Snowtroopers and get to the Falcon. At one point C-3PO finds himself on the opposite side of a door from the rest of the group, C-3PO stands there banging on the door repeating "Captain Solo, Captain Solo" and then gives up and says defeated "Typical" - the door then opens, Han grabs the droid and says "come on!". I'm sure we're all familiar with that scene. It works because of the well established characters and how we know they are to behave. Solo - the scoundrel with a heart of gold and the invaluable droid waaay to prissy to have somehow survived this long in this galaxy. The combination organically makes for good humor.
Flash forward 19 years from ESB and in comes Jar Jar - a character that Lucas many times has said was put into the movie "for the kids". We had no such bumbling idiot character in the OT, not even C-3PO came close. So with the introduction of this character came the sight gags - him stepping in poop, smelling farts, stumbling and bumbling his way through a battle, etc... None of that spoke to the core audience who grew up on the OT and made the OT an event to pass down to their children. Speaking as someone who had a young son when TPM came out who was 10 at the time, not even he enjoyed that ridiculous nonsense. Star Wars movies should appeal to "kids of all ages" not just five year old kids who have spent the first five years of their lives drooling on themselves watching horrible cartoons on Nickelodian (sp?).
I have had many discussions with my friends who are varying ages of 20-50 and we all agree if instead of trying to force (no pun intended) humor into the PT and instead let it come naturally through the interaction of well defined and acted characters the PT wouldn't be as maligned as it is today.
Think about this - what would TPM have been like if Jar Jar had been a noble warrior and former leader of the Gungans, exiled when Boss Nass came into power and when we first see him, with only a staff he is adeptly taking on several battle droids at once and only due to overwhelming odds needed Qui Gon to help him and because Qui Gon helped, he pledges a life debt to Qui Gon for standing next to him in the fight and turning the tide.
Cut out all the ridiculous nonsense and then when you go to Tatooine, allow for some of the humor to come naturally because he could be the proverbial "fish (or in this case amphibian) out of water" in a land with no water or moisture whatsoever. Add that you meet up with Anakin at the SAME AGE as Luke Skywalker, completely avoiding bad child actors and you find a GOOD actor who can actually show other emotions beside "spoiled jerk".
When it comes time for the end with the battle, Jar Jar goes to the Gungan people with the group to ask for help in fighting the battle droid army and finds them oppressed by the rule of Nass and his corrupt council, he challanges Nass for leadership of the Gungans, he is reminded of what happened last time, but this time Jar Jar defeats Nass, liberates the Gungans and they are happy to follow him into battle. Anakin gladly jumps into a fighter and is a great asset in space because of his skills in a cockpit, not because of how many times he can say "wizard" and "oops".
Lastly, you give control of the movies over to directors who can actually direct, not directors who provide direction by saying "okay that was good, but let's do it again, only this time do it better" - what the heck does that mean.
These are all simple things that could have made TPM at least modestly GOOD and watchable. Like Matt said in the previous post, Lucas surrounded himself with "yes men" who were so thrilled to be working on Star Wars they didn't care whether or not the Star Wars they were making was crap - and that is where the team behind the PT lost their way.
I find it awfully petty for Lucas to make that remark about how they wanted Star Wars to be about spaceships and not family drama. Unless Kasdan and Abrams totally throw us a curve-ball, I'm willing to bet that a HUGE part of The Force Awakens will be about family and who your family is. It's just that it will also be about spaceships and explosions, instead of humanoid amphibians doing a Jamaican Stepin Fetchit impersonation and stepping in crap for laughs.