Hello everyone :)
WARNING: Its not a list of problems, but explanations to the "problems" that have been listed above. Also the way I've seen them is: I, II, IV, V, VI, III (since I started with I, but had to wait for III for some time to come out).
-Revelation of Jabba: back when ROTJ came out, it was revelation (wothout huge focus on itself, but still). Nowadays Star Wars are everywhere, so Jabba is well known. When I talk to some people who haven't seen SW, and ask if they know Jabba, they might say "that fat worm-ish guy?". SW are too big nowadays to keep any revelations in OT (at least not at the same level), and it would mean not using Hutts in any other SW product, which is unlikely.
-Training equipment on Falcon: Kenobi had lightsaber (obviously), found some dirty helmet, which is NOT like the one that younglings were using, which is not difficult. So all that's left is training droid, which is small and he could have taken it to train Luke while going to Alderaan and then later (he didn't really plan to be cut by Vader, you know)
-What are Jedi? What's the Force? When I watched Ep.I the way I understood was that Jedi are these dudes with lightsabers and "magic" who maintain peace, and the Force is the "magic" they use to use Force push, be super fast, feel life around, etc. I only got confused by "Sith" a bit, thinking at first that Zabraks are Sith, but with Ep.II it became clear that Sith are "bad Jedi".
-Why in Ep.VI no one is mentioning that Anakin is the chosen one? As we see in Ep.III Jedi have lost their faith in this prophesy.
-Anakin did NOT invent protocol droids, you can see one on the ship of Trade Federation. Darth Vader didn't talk to 3PO even once. He only saw some broken protocol droid with Chewbacca, and 3PO couldn't recognize him ether for obvious reasons (although in some EU comicbook Vader had a flashback to 3PO when he saw him, I believe, but nothing more). There are no positives or negatives in "Anankin built 3PO", just Lucas' fetish for "rhyming in storytelling".
-Owen doesn't recognize 3PO or doesn't even mention him. First is that, indeed, there are hundreds if not thousands of protocol droids and astro-droids, and 3PO looks very different and had memory wipe. And he had only seed R2 once. Why not mentioning it? To whom? Beru? She knows it herself. To Luke? Mentioning that "that droid is kinda like the one your dad had", while trying to avoid conversations about Luke's dad? I don't think so.
-Obi-Wan said that Jedi knights have been guardians of Republic for thousand generations, while Palpatine was referring to the fact that the Republic has been whole for 1000 years, when there were no grand scale wars. Although the way it's said can indeed create confusion, especially in EU.
-D-rings on lightsabers: the design of a lightsaber is just a personal preference.
-Obi-Wan owned R4 unit and that one was destroyed 20 years ago, during battle of Coruscant. Other than that, Ben is one lying individual... or rather one with "certain point of view"
-Palpatine is NOT Anakin's father. Anakin was indeed created by the Force, but only because Darth Plagues and Darth Sidious (not sure if Darth Tenebrous has anything to do with it, but whatever) were able to shift the balance of the Force, believing themselves to be above it in a way. Force clearly didn't like it and created a man who's destiny was to destroy them (Plageous was already killed by Sidious, so only one remained) and restore the balance.
Hope it was helpful :)