whitepawn;
Try this: To start the computer in safe mode:
When you see the message "Please select the operating system to start",
press F8.
Use the arrow keys to highlight the appropriate safe mode option, and then
press ENTER.
If you have a dual-boot or multiple-boot system, choose the installation
that you need to access using the arrow keys, and then press ENTER.
Once you are in Safe Mode your display is going to look goofy, ignore this.
There will also be a little window warning you that you are going in to the
Safe Mode, click OK or Yes. You will also be limited in what you can do.
However, you should be able to get back to the Control Panel to put the
Welcome Screen back. Or to TweakUI to fix your error. I made this same
mistake myself and was able to repair my mistake. When you are done fixing your
mistake, just reboot.
I hope this helps. Let us know.
Wes