HIya,
I got a major problem with my PC everythings fine, works fine 10- 15 minutes then freezes crashes then I have 2switch it off/on, happens every time tried 2install new windows xp but can't complete crashes freezes at setup is copying files. What's the problem first thought it was the registry or bios thus I decided 2install windows again. Please help...

Have you opened it up and blown out the dust?

I have seen this happen when the cooling fan is caked with dust and lint and is unable to cool properly, thus shutting down the computer when it gets to hot.

Could also be the fan has quit altogether?

Good Luck.

Yeah thts the first thing I tried becoz had a laptop and the fans dead so it keeps shutting off but my PC don't shutdown just freezes in the middle of whteva yo doing and now after trying 2install windows reckon becoz it froze half way through formating the hard drive now it won't even let me re-instal says something about 'NTLDR is missing', reckon I can fix this but main probem is the crashing. Pliz help

I found this link for you, hope it helps, it has more information than I am familiar with.

How to troubleshoot the "NTLDR Is Missing" error message in Windows 2000

How to troubleshoot the "NTLDR Is Missing" error message in Windows 2000

I guess we can't post links on here? Anyway, if you can access the web from another computer and just Google the above information,
There is a lot of information available.

Good Luck!