I hate to tell you this, but I've been doing some research on infections that sound similar to yours, and everything I've seen says that this is pretty severe =( As in, I haven't found a simple fix. My suggestion would be to go get a program called SuperAntiSpyware, which a lot of people seem to be recommending. Install it and reboot into safe mode. Run all your antivirus and anti-spyware scanners several times, don't reboot back into normal mode until your system is coming up clean. See if that does it.

Alternatively, get a Mac or Linux =)

The Google has been kinda slow lately, but I think that's because they're rolling out new updates to some things.