I know this full screen problem thing, but Panther has another problem with it's built-in DVD Player. Apple was really proud of it, because they made a video that demonstrated it. In Jaguar, they had this feature where the DVD player would was visible from the Dock when you minimized it.
On Panther, the DVD player doesn't do this. In Panther, it just shows up completely black! It's really annoying, and I know it's not just me, because I have talked to other Panther users and they say their systems lack the feature, as well. This was a really cool feature, and I'm not sure why it has been disabled in Panther.
If anyone out there knows how to enable the minimized dock player in Panther, tell me. I would love to know if it's possible!