Use a firewall – If you have a complete security suite installed, use the firewall included with it. If not, turn on the Windows Firewall. Start > Settings > Control Panel >Windows Firewall.
Install an Anti-Virus software package. & MAKE SURE IT IS UPDATED REGULARLY! If you had an AV software installed when you bought your computer, make sure you are still getting the updates. There are some good free packages available: Anti-vir, AVG Free, Avast Home Edition and ClamAV. AVG is very easy to install, runs a real-time scanner (protects the computer as you use it) and catches a lot of viruses. ClamAV is often awarded for finding the most viruses, but it does not have a real-time scanner, (though you can configure it to run “Scheduled Scans” regularly).
Download an anti-spyware application such as: AdAware, Spybot Search & Destroy or Windows Defender to help clean up and/or stop new infections.
Configure Automatic Updates for Windows. Open Internet Explorer and click on Tools > Windows Updates. On the right side of the window the site will tell you whether Automatic Updates is on or off and how to turn it on. (Look for a “More Options” during the process to choose what works best for your unique situation – especially if you have a “slow” Internet connection.)
Install Firefox. It is free and will protect you from many exploits. Internet Explorer is the most exploited browser, if you avoid using it for daily browsing you will have a more secure system.
Firefox has many plug-ins (also called extensions) that can also help you protect your system. The following are highly recommended: NoScript, AdBlock Plus, FilterSet.G for AdBlock Plus, and Flashblock. These all disable some functionality on some websites, but they do this to stop your system from being infected without you knowing about it. You might have to change a few settings here and there to make some sites work correctly. (Click on: Tools > Add-ons > Get Extensions from within FireFox and then search for these extensions.)
Run Secunia Personal Software Inspector. It is free and it will tell you when you need to update your other software (Adobe Acrobat, Firefox, Java, Quicktime, Real, etc).
Install McAfee Site Advisor. If you installed Firefox as recommended above, you will want to install both the Firefox version and the IE version so that you are alerted when you use either browser. Site Advisor will warn you of malicious sites when you are searching for sites using Google or other search engines. Just watch for the green check or the red X when searching.
Create an every day account that you use that is NOT an administrator account and use it most of the time. You should not use the administrator account or an administrator-equivalent account unless you really need to. (However, be forewarned this may cause problems with older software.)
Use a Local Hosts file from a site like www.mvps.org/winhelp2002/hosts.htm. This will keep your computer from being able to contact over 16,000 sites that distribute software called malware that can steal your personal information, user accounts and passwords.
SecCheck from MyNetWatchman.com tells you what is running on your computer and helps determine what malware might be installed and causing problems.
Virustotal.com is a site that allows you to upload suspicious files to tell you whether it is malware or a legitimate program.
KeePass.info provides software that helps you keep track of all of your passwords.
TrueCrypt.org has software that encrypts your valuable data to protect you from identity theft.
lightspeedguide.com has a free package that you can download and it does a pretty reasonable job of filtering your Internet access to the appropriate sites for your kids