I am no expert, but here is basically the rules I follow when it comes to Virii or Spyware:
FIRST and foremost, make sure Windows is up to date. Alot of virii and spyware are able to get in due to exploiting security holes that have since been patched. If you decide to "clean" first, you are just as succeptable to infection. Patch first
Make sure your AV protection is up to date, same logic as before
Download MS Antispyware, and either Ad-Aware or Webroot SpySweeper. I prefer Ad-Aware, only because it's free, and webroot is only a trial. MS is also free, and provides the real-time protection. After installation, update all definitions.
Download WinsockXPFix. This is CRUCIAL, if you loose your internet connection after removing spyware (see below) there is obviously no way to download it.
Download HiJackthis, run scan, remove all offenders. This will help get rid of some threats running in memory.
Reboot computer, into safe mode without networking. (Virii and Spyware tend to flex more muscle with an enthernet connection to work with).
If your AV is configured correctly, it should be "on-access". This is helpful because say, while you are doing a scan with either M$ or Adaware, if it comes across a virus, your AV will detect it. So, start with M$ first, mostly because I found that is the best for being able to terminate a process if it is running, and remove it. Ad-Aware, and sometimes SpySweeper can't remove some serious offenders until after the next reboot.
If started with M$, run other scan, Ad-Aware or SpySweeper.
Reboot into windows normally, do a scan with Ad-Aware, this should come up relatively clean.
Obviously, some cases are MUCH worse than others, but 9 times out of 10 that has worked well for me. Keep in mind, if any machine is REALLY hosed, the registry might be real messed up, that in combination with the time it could take if the machine is bogged by active processes, you are better doing a re-install if the data is backed up.
Also, sometimes if you remove spyware it could cripple your TCP/IP stack, and that is where the WinsockXPFix comes into play.
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS