Applejack - a user friendly troubleshooting assistant for Mac OS X. With AppleJack you can troubleshoot a computer even if you can't load the GUI, or don't have a startup CD handy
Antivir - a free antivirus program that claims to detect more viruses than any other
Avast Free - another good free antivirus program
Broadband Availibility Checker - find out the availability of ADSL, Cable and Satellite broadband where you live
Firefox - excellent free web browser, safer alternative to Internet Explorer (works on OSx, Windows and Linux)
Foxit PDF Reader - a smaller and quicker open source replacement for Adobe Reader
GRC.com - Gibson Research Corporation - many handy security tools, including the Shields Up! firewall analysis service
Microsoft Baseline Security Analyser (MBSA) - a Microsoft tool for detecting vulnerabilities in Windows, Office etc
OU Safe Computing List - an excellent free resource from the Open University that tracks security threats and how to avoid them
Spybot Search and Destroy - anti-spyware utility with preventative immunization
SpywareBlaster - an anti-spyware program that prevents spyware from getting onto your computer
System Information Wizard - a very handy program for analysing the hardware and software of Windows PCs
Windiz Update - an alternative to Windows Update for the Firefox browser (requires a plugin)
Windows Defender - Microsoft's free anti-spyware software (requires Windows Genuine Advantage check)
Windows Update - if you don't have Automatic Updates enabled make sure to check here often
Windows Vista Upgrade Advisor - check whether your hardware can run Windows Vista
Zone Alarm - a good software firewall that has a free version for personal use
**********
If I am unable to help, these online business directories may help you find someone who can: