SUPERAntiSpyware is an easy-to-use tool that will quickly scan your entire PC for spyware, then remove anything it finds at a click.
The program can check your memory, Registry, startup locations, cookies, and all (or selected) folders on your PC for potential threats, and is able to uncover everything from tracking cookies to trojans, rootkits to rogue security products.
This portable edition is designed for running from CD or USB flash drives directly on an infected PC. Download the latest version - which includes the latest signatures - by clicking the link above and either burn it to CD or save it to USB flash drive (which should be write-protected before you insert into the infected PC to prevent the drive itself becoming infected). Introduce it to the infected computer - the scanner is given a random filename to help evade detection - and then let it do its stuff.
The portable version offers the same scan and remove features found in the free version, and could be a lifesaver - if it won't run in Normal mode, boot into Safe mode instead and run the tool from there.