You have to watch out, some of those virus removal sites are virus installation sites!
Often you anti-virus program’s website will have the best info, or zdnet.com (I think). Or if you’re unsure, search for blogs on the subject and you’ll get legitimate answers.
If you choose a removal tool you’re unfamiliar with, search “(name of the tool) Reviews”.
Disclaimer: I'm a Linux guy. Used to be a MS guy starting with DOS 1.0 back in the day. I've worked with a variety of different systems though.
That said, I gave up on MS back around the time XP was coming on line. I'd already been soured back with Win95 and their IE integration and ActiveX security nightmare. Security wise, MS seems to look at it as an afterthought. Totally disregarding all the lesson learned from a multitude of platforms and environments dating back to to the first multi-user systems.
Ideally, virus removal would be best accomplished via a boot CD with a known clean and up to date virus software and definition file. The problem with working directly from an infected system, would be like trying to develop a human vaccine in a compromised room. You also have to consider that virus authors are getting more sophisticated, and are taking countermeasures into account.
Now that is the ideal scenario. More often than not, you are left using your infected system to clean your infected system. And while the right software can do the job, you'll still be left with that nagging doubt as to whether you got it all or not. Just like excising cancer from your body.
Something you can do with a computer that you can't do with, well, YOU - is wipe the system and start from scratch. Or as I like to say, stealing a line from the movie Aliens: "Let take off and nuke the site from orbit; it's the only way to be sure."
And again, ideally, once you feel you've cleaned your system, and you feel you can take your important data off of it? Do so, then take off and nuke the site from orbit. Or as we in the biz like to say: reformat and re-install.
A pain in the @$$ - YOU Betcha! Trust me I know. But given the registery, .dll Hell, and all that, that's the only real way you can ever really be sure.