For a fast small portable malware removal scanner try superantispyware portable edition scanner. It is free and can run from the infected computer's hard-drive or from a USB drive. Often malware and other bad-ware will disable internet access or sites that contain tools that can clean the computer.
Superantispyware portable does not need to be installed and can run from a USB or other drive.
I have used this program often over the years and even before they had the portable edition. Works very well.