Virus

my sons pc has got a virus of some kind wen i start it up it says windows xp recovery and starts to scan computer then says crictal hard drive error then says ram is full if any 1 has any ideas to get rid of this virus it i would be very greatful ty .

Hi villa32. Do you have any control over the computer while this is happening?
This message that you see, is it after the computer starts up your desktop?

If it is and you can still connect to the internet then download and install Malwarebytes

Once installed either reboot your computer into safe mode (done by rebooting and pressing a function button like F8, F6 or so on until you get a list of options, one being safe mode) or if you are unsure how to do this then run A FULL scan in normal windows.

Once the scan is finished it will report the list of infections found and depending on what you want to do with the results you may have to restart. Quarantine or delete the infections found.

When you restart (or boot into safe mode again) run another full scan with whatever antivirus you have installed.

Make sure both malwarebytes and antivirus are kept up to date

as well, if you can,download and run hijack this and post a log.another thought is to try a system restore to a time before this all happened.keep in mind that this may just give you enough functionality to run these other programs and may not totally solve your problem.