Welcome,
About the best scanner that I've found that will clean itself out of a system after doing its job is the eset online scanner
http://www.eset.com/us/online-scanner/
I'd recommend using a two step process of having the scanner identify all of the problems and then reviewing the list before allowing anything to be deleted.
The best way to clean a system is to work with one of the trained volunteer staff at the free malware removal sites listed
http://www.bleepingcomputer.com
http://forums.whatthetech.com/
http://www.geekstogo.com/forum/
http://www.cybertechhelp.com/forums/
They will have tools that need to be installed long enough to identify the problems but everything can be removed once the system is clean.
I am assuming that there is an active security product installed and that it will remain and be kept current.
Keep us posted