if its that bad reformat and take a ghost image once the machine is up and running.
I have very little time for customers of mine that allow their system to get virused up to the max as it were and unless there prepared to pay 15 quid an hour for me to sit there watching a boot time virus scan then id just format and tell them off for downloading garbage
Dude its obvious you put yourself accross as a system builder you should know what to do