First, thanks to all for the suggestions and assistance on how to fix this.
I`ve updated my drivers,to version 6.1.77 (dated july 04 I think). This looks like the last official nvidia drivers for my old TNT card. So far, everything seems to be ok. Further to other suggestions, I think I may be having a overheating problem. It has been a particular hot spell here in the (usually) rainy UK. (ignoring the flash floods in yorkshire
)
I`ll be getting more RAM (to bring me to 512) and a nice new (and improved fan) for the CPU. Graphics card update is definately on the cards, put will probably have to wait...
Once again, thanks for the help. Now, onto the battlefield