I have to say, of all the Transformers origin stories, I think I like the G1 cartoon version the least -- even less than the Bay movie backstory. In the original comic, the Transformers were created by Primus, who was a giant good robot god from another dimension battling the evil god Unicron. If I remember right, they each crashed into an asteroid. They fused with each asteroid, and Unicron got his planet alt mode while Primus became Cybertron. The purpose of the Transformers was the battle Unicron.
In the cartoon, the Transformers were simply products created by an evil group of five-faced tentacled aliens called Quintessons. They were built on Cybertron, the Quintessons' robot factory. The Decepticons were military hardware, the Autobots consumer goods. They revolted and drove the Quints off Cybertron, then the military robots decided to conquer all.
Even the movie backstory of the TFs -- what we know of it so far -- is better than having goofy-looking evil aliens being their creators. I'm a TF fan from childhood, but as far as I'm concerned, the less of the cartoon backstory they use, the better.
Re: Pretenders, this was probably the second dumbest gimick of the G1 era. The backstory of the Pretenders for the toys (they never appeared on the cartoon) was that they needed to disguise themselves as humans. The only problem is that they hide inside these super fat 50' tall human shells, so it kinda made no sense. The one cool thing about the Pretenders is that they included newer versions of older characters that were no longer available in stores like Jazz, Bumblebee, and Grimlock.
The dumbest of all, backstory-wise, has to be the Action Masters. They were Transformers that didn't transform into anything. While they were pretty cool looking figures, and more poseable than most regular figures, the backstory made even less sense than the Pretenders' backstory. On the commercial, Optimus Prime has assembled his troops and announced that to win the war against the Decepticons, "We must give up the art of transforming." Say whah? Why don't we just give up our weapons while we're at it, Optimus? Hasbro wasn't putting a tremendous amount of thought into that last line of G1 products.
EDIT: To those who were offended by the twins, evidently Orci and Kurtzman share your pain
Cole: I heard that the gold tooth was Michael Bay’s idea, but do you have any response to those who found The Twins offensive?
Orci: Number one, we sympathize. Yes, the gold tooth was not in the script, that’s true.
Kurtzman: It’s really hard for us to sit here and try to justify it. I think that would be very foolish, and if someone wants to be offended by it, it’s their right. We were very surprised when we saw it, too, and it’s a choice that was made. If anything, it just shows you that we don’t control every aspect of the movie.
Cole: Were you offended by them?
Kurtzman: I wasn’t thrilled. I certainly wasn’t thrilled.
Orci: Yeah, same reaction. I’m not easily offended, but when I saw it, I thought, ‘Someone’s gonna write about that.’”