Display Issues w/ Unattended Install

I can't for the life of me figure out what's happening, but for some reason after I install from my XP unattended I start to run into some issues.

It always seems to happen after I play a round of Imperial Glory (I'll try their support, too), but rebooting among all the other common solutions for video issues doesn't reset it back to normal.

What actually happens: I close Imperial Glory after playing for a while and the screen goes black to reset the desktop. The wallpaper image will suddenly disappear and the desktop becomes the theme's standard background color. From that point forward, Firefox (1.0.3, but I've also tried 1.0.4) won't draw correcly, either (website won't show at all, various GUI components will be invisible - anything that changes w/ mouse over will show after I've moved the mouse over them). Explorer also seems to "lag" during drawing of it's windows (when first opening any folder, and each time I navigate through folders within one window).

My first experience with this, I removed the "unsigned dll" that's installed with nLite. The issue still occurred. I then tried it without removing any components (drivers, services, etc.). I've tried it without applying any video drivers during XP setup (installing Catalyst after first boot).

Does anyone have any suggestions as to what might cause this issue? I haven't tried any other games, so I can't confirm this happens only with Imperial Glory (why I'm asking here). Turning off Theme support doesn't work, either, and I've neither does having ThemeXP installed (even though I use a standard XP silver theme with a custom wallpaper).

I'd appreciate any suggestions, even guesses. I'm sure there's a ton of stuff I'm just not thinking of. TIA