How would i go about wipeing my computer clean and start again installing xp, am sure ive got a virus on it and if i take it to pcworld they said that they would have to delete everything so how would i do it myself

Just pop in an XP disk and reboot the computer. Part of the install process is wiping over anything on the hard drive. This would include any virus/worm/trojan.

Have you tried all other means of getting rid of this virus ?

yes ive tried repairing it and all sorts but no look

What makes you think you have a virus?

Assuming it's XP, boot up with the recovery disk in the CD drive, and then select Option 3 when the recovery screen opens.

If you have a virus, why don't you just do an antivirus scan. If you need a good free one, then AVG does the job.

XP is quite good at recovering and a virus will be removable. The reason PC world say take it in and they will wipe it is because they are all numpties. They can easily flatten it and restore it in no time and with no skill what so ever so it's perfect for them. What is actually up with your computer? Why do you need to wipe it and start again?