If you don’t have an installation/repair disc, you can make one with these instructions.Click next on the next screen, and then choose System Restore from the System Recovery dialog.
To get into Safe mode, you can reboot and use the F8 key right before Windows starts up.
If the F8 key doesn’t work for you, you can force the system to go into safe mode by following instructions from Larry in the comments.
If Your System Won’t Boot If you can’t even get into windows, you can boot off the installation dvd, and choose the “Repair your computer” option on the lower left hand side.
Windows 7 and Vista has a feature called System Restore that automatically backs up registry and system files whenever you install new software or drivers.
This feature is useful when you install evil software that makes your computer run really slow. You will immediate see a screen where you can choose to roll back the system to the last restore point.
But don’t worry, System Restore won’t remove Windows Vista. You can select “Recommended restore”, and just click next, or you can choose a different restore point.
If you do choose a different restore point, you will see a list of restore points that you can choose from.
How many times have I typed the word choose at this point?
You’ll notice in the screenshot below that the last thing I did was install Virtual Clone Drive to mount ISO images, but right before that I installed the NVIDIA drivers.