ctfmona virus?

somehow, probably through a dodgy download, the ctfmona virus infected my computer (bugs crawling across screen, blue screen saying warning - your computer has been infected with spyware...!). at the time, stupidly, I didn't have any anti virus protection. following advice from searching forums, by downloading norton anti virus and superspyware, i think i have deleted it as it isn't found in a superspyware scan, and it isn't present in the registry edit anymore but i can't be 100% sure as I don't know that much about computers - does anyone know a way I can check? when researching this i've found lots about doing a hijackthis log but i've no idea how or what this means.
since it happened, my laptop has been really slow - any advice? does this mean the virus is still there?
also, when running superspyware again, it doesn't find cftmona but it does find adware tracking cookies - are these normal or part of the virus?
one website i found said that even if you think you've removed ctfmona you should think twice about using the computer again for anything involving passwords because part of the virus will always be tracking you and therefore your security will always be compromised. is this true?
any help would be greatly appreciated!
Bubble