i have reformatted the drive as i wanted to do this anyway but this didn't help i have installed the latest driver and MS packs and updates.

So you installed the latest driver for what? Do you mean Service packs?
Otherwise, look here for the latest drivers:
http://www.nvidia.com/content/drivers/drivers.asp

By your PC freezing I gather you mean that you do not get any blue screens.

If a Clean Install of windows XP does not fix your problem then I can venture to guess that one of your hardware components is failing or dead.
The best thing you could do is re-install windows XP on a MIMINUM amount of hardware....which means just the System board and CPU with ram and video card. Apply all the drivers (including motherboard drivers) and patches.
Then switch off the PC and add the sound card (or enable the sound chip if onboard). Do not install any other hardware, eg: modem or network card.
Try to run your games now, and if your PC still freezes try a different video card or a different ram stick. Basically find the faulty piece that is making your PC freeze.
No need to mention that heat is also a common cause of PCs freezing.....so find out what is not being cooled properly or if a heatsink or fan has slightly come loose.

Cheerio

An XP1700 that's 18 months old is likely to be a Palamino. They run a tad hotter than the later Thoroughbred XP1700s, and I'd be checking that the initial installation of it hasn't used silicone based thermal compound. If it has, it's likely to have dried out by now and become less efficient. Removing the heatsink, cleaning heatsink base and processor die, and replacing it using a better quality compound would be a good idea for a system of that vintage.

Here's the instructions from 'Arctic Silver' website. Try to avoid using the white silicone based crap that you get cheaply from electronics stores - it's nowhere near as good as a decent thermal compound.

http://www.arcticsilver.com/arctic_s...structions.htm