This is how you fix the problem.
In Display Properties change the display adapter to Standard VGA Graphics adapter.
Reboot to Safe Mode.
In Device Manager delete any display adapters listed <b>except</b> the one you just installed, Standard VGA adapter.
Reboot and start Windows normally.
Windows may automatically load your nVidia drivers. If it does things might appear just the same as before, 640x480 by 16 colors but with one difference. This time you will be able to change the resolution and color depth.
Alternately, Windows may start in VGA mode and you will manually have to reload your drivers. Again, you may get 640x480 by 16 colors but you will be able to change this.
<b>99% is great, unless you are talking about system stability</b>