1. Note how utterly derailed this thread has become. Discussion of screenwriters transformed into an argument about whether a corrupt Sith politician is a better villain then an insane pink teddy bear.
2. They were both well written villains. Toy Story 3 was an enjoyable, family-oriented, animated film. Star Wars is an enjoyable, epic space saga filled with Lightsaber-wielding warriors and politicians with Force Lightning*. Comparing the two is like comparing an apple and an orange. It isn't which is better, it's which you enjoy more.
On a side note, it is ironic: Pretty sure that neither Disney/Pixar OR Lucasfilms planned on a second film**.
*: Referring to SW as the Films, not the Films+EU. Toy Story doesn't have any backgrounds like the EU that Star Wars does. Quite frankly, I know of a lot of people who would gladly forfeit the EU of Star Wars and have the Force be as mysterious as the reason for why the Toys are alive. These are not my personal views, however.
**: Technically, Lucas DID have a backup plan: If the first Star Wars movie failed (ROFL) he had a sequel written to try and revive it. The sequel evolved into a book whose name escapes me.
actually Star Wars and Toy Story are closer then you think. First off they are BOTH family fun adventure films. Remember 5 of the Star Wars movies are rated PG. (one of them even has poop jokes) The Prequels are animated films at these point with entire battle scenes completely done in a computer. The entire gungan vs the Battle droids battle is completely CG same with the Clones vs the Droids on Mustifar.
The special editions are getting close to be considered full animated films at this point with the crap ton of crappy cg animated stuff added.
Look at the main characters
Woody is esential Luke. Instead of the force Woody believes in Andy and working for Andy.
Buzz is Han.
Pig is R2D2
T-rex is C-3PO.
really Toy Story 3 IS a star wars movie. Just keep the plot the same and replace the places with alien worlds and there you go.'
edit: you are thinking of Splinter of the Minds Eye, the book sequel that Lucas had written.