Well, they're both very different animals. I love both Eddings and Feist, but I have to say that Magician would make a better film, simply because Feist's characters, while being great in and of themselves, are different than Eddings' characters. Eddings takes great time to develop his characters carefully, whereas Feist tends to make bigger strides in time passed, allowing a broader picture of his characters much faster. It doesn't make his characters any less valuable, just easier to translate into film characters. The audience could get to know Pug in a 2 hour film much easier than they could Garion, and the writers for the film would have a much easier job too. Magician is already fast-paced enough to put into film too. If they can film LOTR, they can do Magician. I don't think I'd want PJ to do it, though. Give it to someone else. The only other director I know of to do fantasy is Ron Howard, but I don't think I'd want him to do it either. Maybe Rob Reiner.
A note on the books:
Magician was originally released as a single volume. In recent years, Feist sought to re-release the novel in two parts, calling them the "Author's preferred edition" (basically he'd made enough money to override his editor). Now, just within the past year or two, he re-combined them into one volume as the author's preferred editon of "Magician" made whole.