As you may have read earlier support for Windows XP service pack 2 ends tomorrow, therefore you should seriously consider installing SP3, however some users cannot upgrade to SP3 due to program incompatibility etc.
If you are one of these users ComputerWorld have an article well-worth checking out, it explains some ways that you can do your utmost to stay secure, which is extremely important as SP2 will soon be open to a wide-range of vulnerabilities.
The first thing you must do is ditch Internet Explorer, personally I would completely remove it from my computer via XP’s control panel, however you must ensure that you have installed an alternative beforehand.
Web browsers worth checking out include Mozilla Firefox, Google Chrome, Opera and Safari, click on one of the links to download one now. To remove Internet Explorer uninstall all versions and service packs from add/remove programs, also untick Internet Explorer box on the add remove windows components screen.
There are also other Microsoft applications which you should replace, such as Windows Media Player, iTunes is a good alternative. If you use Microsoft Outlook express you may also want to try a different mail client such as Mozilla Thunderbird.
If you check out the source link below you can find out more XP2 Security tips, including updating your third-party applications and plug-ins.