Looks, from Googling, like spyware.
1. Google removal tools - there appear to be loads about.
2. Check your current firewall, anti-virus programs are working properly, if not make them work or change. Then make sure they're properly configured, and not only stop stuff comig from the outside world, but block non-essential stuff going out i.e. only allow HTTP and HTTPS traffic if you use web-based mail services.
3. Consider K9 from Bluecoat -
K9 Web Protection - Free Internet Filtering and Parental Controls Software
4. Use Firefox, and install FlashBlock, NoScript and SpoofStick extensions.
5. Check your C/card hasn't been debited - if so, dispute the amount.