Fedora :: F14 XFCE Meltdown After Browsing Desktop Themes?

I installed Fedora 14 XFCE last weekend on my laptop..been putting in a little time here and there into customizing it, as I was trying to make it my new main OS, when suddenly today it suffered a complete meltdown that I have no idea where to start in trying to fix it. All I was doing was browsing through the desktop themes. I hit a certain theme, don't know which one, and the screen went blank. X then looked like it was trying to restart, then blank again. Then X looked like it was restarting, and blank..and repeat endlessly. I tried turning the laptop off and then turning it back on again.same result. Now I basically have a dead system, practically speaking, because I can't use it.

Putting aside the fact that it is immensely frustrating to have a Linux OS choke and die on me just from browsing through the preset desktop themes, does anyone have any idea what I can do to fix this, aside from doing another fresh install? The only way I can think of to fix it would be to login into some kind of rescue mode (which I don't know how to do), get to a shell prompt, find the right config file (which I have no clue about, either), and fix the settings to where it will at least boot up, then I can select the default theme and never touch the themes again.

After that I suppose I should put in a bug report or something to Fedora about this -- that is, if I can reproduce it. Maybe that'd be at least some compensation, since I had high hopes for Fedora when I decided to try it, but this sort of crash-and-burn is just utterly disappointing.