uninstalling current drivers for such an old card is recommended but with newer cards
sometimes you do not even have to go through all that.

anyways with the nVidia driver install just choose the 'custom install' option then under that select perform 'clean install'.
downloading the current drivers ahead of time is def a wise move.
if Win7 and active internet connection Win Update will get the drivers for you, if an XP machine I have forgot if you have to do it manually or not.

cheers.