From Daavee,
here
You have Windows XP Gold (no service packs). It is actually risky to have it connected to the Internet. In its present state, it is not secure and malware can slip in. Actually, a hacker could slip in...
I recommend that you use another PC to download four important installation files (mentioned below) to your USB flash drive.
Preliminary work:
Download the installation files for SP2, SP3, IE8, and Microsoft Security Essentials, which is an effective antivirus/antimalware program. I prefer to keep these (and other useful files) on a USB flash drive, but that part is optional. Here are the links for all four installation files:
http://www.microsoft.com/en-us/download/details.aspx?id=28 (for SP2)
http://www.microsoft.com/download/en/details.aspx?id=24 (for SP3)
(You may TOTALLY disregard the "intended for IT Professionals" message!)
http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=43 (for IE8)
http://windows.microsoft.com/en-US/windows/products/security-essentials (for MSE)
1. Physically disconnect from the Internet. Also disconnect all unnecessary peripherals!
2. Temporarily disable Automatic Updates. To do this:
Start | Control Panel (switch to Classic View if not already selected) | Automatic Updates
Select "Turn off Automatic Updates" and click OK.
3. Install SP2. Reboot TWICE.
4. Install SP3. Reboot TWICE.
5. Upgrade to IE8. Reboot TWICE. (Note: It is important to leave IE at the IE6 level before upgrading to SP3. After you are at SP3, then you may upgrade IE6 to IE8.)
6. Install MSE.
(Very often what happens is someone has their antivirus program running while they are trying to install SP3, which often results in chaos! That is why it should be done AFTER SP3 and IE are installed.)
9. Make sure Windows firewall is enabled (it should already be):
Start | Control Panel | Security Center
(Now you can physically reconnect to the Internet. Update Antivirus program.)
10. Visit Windows Update to download and install only critical security updates. Reboot whenever prompted.
11. Re-enable Automatic Updates.