Game window disappears

For some reason, my game is now set to run windowed. If i try to change it back to full screen, the game vanishes from my desktop and taskbar but remains running.
Every time this happens i need to go terminate javaw.exe, and it starts windowed again next time I launch it.
XP Professional Service Pack 3
Pentium 4
1GB RAM
RESTARTED STEAM
RESTARTED PC
VERIFIED
REINSTALLED
CALLED THE COPS
SUMMONED BEELZEBUB
Still happens.

It didn't work because you didn't sacrifice a 6-pack of mountain dew..... this is Modem gods 101.
Anyway ------
http://wiki.spiralknights.com/Technical_issues_FAQ#I.27m_getting_a_black...
The game stores video settings in the registry, so its a good way to modify it when OGL isn't cooperating. You'll want to set it compatibility mode and full screen first to minimize things it can mess up on. Once you get it running you can turn up the settings via the in-game menu one by one to make sure it behaves.

Excellent, I failed to read a sticky, how do i delete threads.

Just edit the top post and move it to the graveyard if you want to dispose of it.

Okay, it just opened windowed again after changing the registry values.
Tried twice, double checked to make sure the registry value was saving. It resets the value to false when I launch.

whats in the projectx.log file? And what version of catalyst are you using?

projectx.log
http://pastebin.com/qe6Tb4Tf
I'm not sure what you mean by Catalyst. i AM using an ATi card and my video driver is the Catalyst Control Center. But I don't know how you would have known that.
Anyway, My card is an X1650, the drivers are stored in legacy archives. I feel i am using the most recent version.

ATI has been calling their drivers Catalyst for years, just like nvidia calls theirs Forceware. Anyway, the drivers are not responding correctly to the full screen mode change... and I won't lie, it could be any subtle changes in or outside the game that lead to this.
The easiest place to start is just reinstalling the SK client. Then reinstall the video card drivers. And if either doesn't work, we can try digging into more logs.

Driver reinstall did it, this issue is TOAST.
Use Section 5 from here to navigate to the registry settings for Spiral Knights and set the fullscreen value to true.