[andrewas]

With extreme care, thats how. Cookies are safe, nothing depends on them to function. Losing a good cookie just means you have to log in again.

Damaging your registry can kill your machine stone dead.

That said, start->run->regedit will get you into the registry. The programs adaware and spybotSD will remove many malwares from the registry without you having to do anything by hand. A virus scanner is a good idea as well. MSconfig gives you a safer way to disable startup entries, again without neccesitating you altering keys by hand.

If you do have to go into the registry for some reason, see if you can find an automated tool to do it - almost all major viruses have a symantech fixtool to remove them - or a step-by-step guide. And take a backup before changing anything.