1) Install a firewall.
The good news is that WindowsXP comes with a firewall. Of course its disabled by default.
Step one is to install it.
Learn How to install the firewall
2) Install a virus checker and run it.
There are several good virus checkers. Unfortunatly I haven’t found a good free / open source virus checker. So you’ll have to add a yearly subscription to a Virus checker into your Cost of ownership for Windows.
Actually, Grisoft have a free virus checker for home users, www.grisoft.com/us/us_dwnl_free.php
I haven’t used it myself. Anyone got an opinion?
3) Turn off all those services you don’t need.
WindowsXP has a load of stuff running that 99% of home users do not need. Why? Well Microsoft like to be able to show customers that you can just plug your PC into a network and everything will just work. Of course the don’t demo how easy it makes things for people who want to get onto your system.
Some bloke called Blackviper has a complete list of the what you need and what you don’t
here.
4) Don’t use Internet Explorer
Internet Explorer is more full of security holes than swiss cheese. It’s better to use a 3rd party browser. Firefox is the one I would recommend
Get it free here Mozilla.org.
5) Don’t use Outlook (or Express) or ensure its patched.
Ditto, for OutLook, use something like Thunderbird.
6) Install MS updates
Microsoft has a service to update your system with patches etc. Its called windowsUpdate and you should have a link for it in your Start menu. Run it regularly to keep your system patched.