Generally, just re-installing windows or trashing your registry keys (and repairing/reinstalling) is enough to *insure* that you wiped out the adware.

In general though, there are less drastic solutions.

I use my machines for work- which involves a lot of web dev. I also sit on one of the most assulted nets in the world -CMU, where script kiddies go to school to try to be Real Hackers. So I have to watch my systems like a hawk (and, to be sure, I have been nailed PLENTY of times).

A particularily good 'brute force' tactic is to open up a processes list through Task Manger. Then look for anything you think is suspicious. Copy that string into google, in about 5 hits you will find out what the process is for.

Worry slightly if you find out it is adware or spy ware.

If it is, try the following:

First, see if it is on your Add/Remove programs list in your control panel. Remove it.

Next, seach C drive (find files) that match the string "Foobar".exe, where Foobar is the name of the unknown process.

Find where it is. Look at its context (the folder its in, other file names that are bundled with it). Google those and learn what you can.

delete it from you hard drive. Use a file shredder if you are paranoid.

If you are SURE its parent folder is not a system folder, or related to the legitimate operation of windows, shred that too.

Also, look in your registry under 'run once' and 'start up'. google everything there.

If you google a system process and find NOTHING AT ALL, chances are it is NEITHER legitimate windows business nor legitimate software NOR spyware- which means its *possibly* even more nefarious (like a deliberate attack on a network machine or a hackers work). Delete at you own risk, though. If it was legitimate system software, you could be wrecking your OS install.

NEVER try to 'nuke back' a system process (delete the .exe files and etc) until you have studied it as much as possible.

In my experience, You CAN root out spyware on your system. Trying to do so is a good way of learning how to own your own system- however, this is just my experience and you may find it easier to just dump everything and re-install. On work-machines, thats not really an option though!.