Computer Security

Okay, you probably know that you should have an anti-virus program running on your computer that you keep up to date and regularly use it to perform a scan of your system.
Unfortunately, that is the very least that you should be doing to insure you and your data is safe on your computer. PC World magazine recently published the best article on computer security I have ever read. You should definelty read it. I guarantee there are real threats out there that you never even thought of.
PC World article "11 Hidden Security Threats".

Back to this issue of anti-virus software, with numerous excellent, free options now available, there is no legitimate excuse not to use one. If you think that it isn't necessary, then just ask a room full of people how many of them have had a virus of other malicious software cause havoc on their system. I currently use Microsoft Security Essentials on my laptop. It is non instructive. I have used AVG Free for years and currently have it on my desktop computer, but it constantly tries to convince you to "upgrade" to a paid version. I have also used Avast Anti-Virus and Anti-Spyware in the past, but was annoyed by the audio alerts to scan my system. That being said, if you like to be reminded to run the scans, you will really like Avast!
Of course, there are plenty of other commercial products on the market that may offer additional features and possibly better protection. That being said, I have been using free products for years and have been very happy with their performance which is to say, I haven't had any virus problems.

If you are having weird computer problem, I would suggest your using an online safety scanner. There are two that I am aware one. I have used Microsofts's Windows Live OneCare safety scanner a number of times. It will search for virus, all manner of malware, registry errors, and it will also defragment your hard drive and give you the option of deleting unnecessary temporary files.

Trend Micro, a legitimate provider of computer safety programs, has a similar online scanner service named  Housecall. I haven't used it, but it is highly regarded.