Now you have to get a good anti virus
Download microsoft security essentials, it will give you real time protection
download Malwarebytes, use it for a once a week scan. You will have what I use Anti-Malware, Virus, Spyware Protection | Microsoft Security Essentials Malwarebytes : Free anti-malware, anti-virus and spyware removal download
and because you seem like a nice person.
To maintain your computer 10 Tips on How to Properly Maintain Your Computer
Steps that I did not notice on the guide include:
Running a scan disc before doing a defrag
Using Microsoft Security Essentials and Malwarebytes.
Making System Restore points, at least once a week
Makaing a system Image once a month (varies by user)
Not relying on your A/V common sense, should prevail. You know of many sites can cause a problem.
Do not use any reg cleaning or optimizing software.
Download and use Ccleaner about once every two months. Untick any registry entries. http://www.piriform.com/
If you follow these instructions, you will be trouble free for a long time to come.
Be sure to back up your hard drive about once a month (varies by user) and to keeep system restore points up to date. Speed Up the Performance of Vista