In addition to a good antivirus, I strongly recommend Spybot and the resident Teatimer program it
comes with. Teatimer watches your registry and will inform you when anything is trying to change it.
Spybot is free to individuals and an excellent program. Here is a link where you can download
it:
http://www.safer-networking.org/en/home/index.html.
Last fall I got the Virtumonde trojan, which is very malicious and only with the help of the Safer Networking
site (home of Spybot) was I able to get rid of it.
Another wise thing: keep up your Windows updates, if you have done so religiously, you won't have trouble
with the Conficker.
L.
Edit: Let me add a couple of internet recommendations: Adblock Plus and NoScript free add-ons for your browser. These will give you
control over most of the crap the web sites try to do. You can selectively permit known good sites and temporarily or permanently
block others. Also, use your Tools menu to list and delete all cookies, and then set it to allow cookies. Visit all your regular web sites
and acquire your logon cookies, etc. next. Then change the option to allow cookies only for the session and/or inform you about each
cookie. This will keep your tracking and spyware cookies to a minimum, and regular runs of Spybot will keep them cleaned out. Note
that Spybot lets you "immunize" against common spyware problems.
Finally, never never never never never allow any "free registry scan" by anyone. Never! Many of these free scanners are bogus, and
either designed to find non-existent problems, or sell you a program, or INFECT your computer.
If your computer is infected, some of the really bad stuff will block updates to your antivirus, also to Spybot. For example, Virtumonde
makes Spybot update checks always say "no updates available", and does a bang up job of reinfecting again and again, using one of
Microsoft Internet Explorer's own special software "objects". This means you may need to go get and re-install your browsers to
stay clean.
"The question of whether a computer can think is no more interesting than the question of whether a submarine can swim." -E. W. Dijkstra