Lets set some things straight. I have been working on an Eisner vs Iger vs Roy site, and I have heavily researched these things.
First: To people that think Iger and Eisner are extremely different: They aren't. Their pre-Disney backgrounds are similar, and they are very close personally. There is no doubt Eisner picked Iger to succeed him.
Second: Eisner was a great CEO. He saved the company. If Eisner hadn't come to the company, it would have been broken up and sold to the highest bidder. He is also responsible for the huge explosion of growth and diversity in the company. He was the right person for the job, and did great things for TWDC. The loss of Wells, however, hurt his productivity.
Third: Roy just wants the magic to be the same as it was. He knows that Eisner's hands have been tied by the board for a while, and that is what he is fighting against. Not really Eisner personally, but the board as a decision making body.
Fourth: The lawsuit is the correct play, as if it goes ahead, it will most likely create another "two headed" company, Iger and someone else, such as Ed Catmull, or maybe Katzenburg back to run the company along with him.
The reason Roy didn't come to the ceremony is most likely because he has been unhappy with the board for a long time. Why make a statement in front of them if you don't agree with them?