Did you physically remove the card, and/or uninstall the drivers for it?
You should uninstall any drivers you currently have, download new ones from:
http://www.nvidia.com/Download/index.aspx?lang=en-us restart and install the new ones...
The freezes might be totally irrelevant to your graphics card problem, even though they seemingly relate to your BSOD fixing... You could want to run
Memtest86(download, use a CD burner software, for example
CDBurnerXP Free, to burn it
as an ISO image, not just place it on a CD), RAM pretty often causes random freezes... As well as blue screens...