For the past few days Google search links have been redirecting to advertisment sites and they have also been randomly popping up when browsing (firefox).
To run the tool, double-click it (XP), or right-click and select Run As Administrator (Vista).
When prompted to run the scan, click Yes.
GooredFix will check for infections, and then a log will appear. Please post the contents of that log in your next reply (it can also be found on your desktop, called GooredFix.txt).