Why?

Well, nobody wants to get Viruses, right?  Most viruses are just nuissances, but many can be very harmful to your computer's software, operating system, or possibly even your hardware (yes, viruses such as Chernobyl can actually destroy your motherboard's BIOS, and if it's a non-removable, non-flashable BIOS, you'll need a new motherboard).  There are a lot of virus protection programs out there. By default, the anti-virus programs have a huge amount of overkill that can often slow your computer to a C R A W L!  I'm not going to recommend any particular programs, but I am going to recommend some ways to use them that will prevent them from causing more damage than the viruses themselves can. :)

How?

1. Install your anti-virus software with a very basic installation. Ignore their schedulers, background scanning, email scan (this one you *may* want to use, particularly if you use Outlook), and on access scanning. In particular, the on access scanning can really slow your computer down - i.e. anytime you copy a file, it scans that file for a virus. While this will make sure you don't get a virus, it can also be very effective in slowing your computer down so that it will feel like it is half as fast as it really is. 

2. You may now be wondering, how will my computer be protected from viruses if I don't install these options? Well, it *won't* be fully protected.  However, you can add a monthly, weekly, or nightly scan of your computer for viruses that should find and effectively remove all viruses from your computer, without slowing you down at all. How often you have it scan depends on how fearful you are of viruses.  I would suggest using System Agent (the little icon in your system tray with a little clock on it) to schedule these scans. If you leave your computer on 24/7 like I do, you can just have it scan overnight. Most virus protection programs have command prompt versions of their scanning engines. Look at the Help documentation to find out what command line options you need to use in System Agent.

3. If you follow this procedure, your computer won't be fully protected, but it should be able to find and elminate all viruses that may appear.  Keeping your Virus list files updated is also important so that those scans will find all the newest viruses too.  Your computer will now be quick and also protected from viruses.