Should have mentioned
My current driver version is 175.19 - this is the version I was directed to by the search engine on the nVidia website, and I'm running XP Pro SP2. My computer otherwise meets the spec for WinSP, and as I say, I had no problems with my old onboard Intel graphics chipset. I would simply go back to using that chipset, but I would need to physically remove the nVidia card to do so - a hassle I want to avoid.
As an aside, I'm not sure if having the latest drivers is a good thing - I have read that the newer drivers are part of the reason that this card does not get on with older programs (if that is actually the problem I am having here)