Spyware on my PC, Rebooting didnt work!!!

I had TONS of spyware on my PC, the ad aware and spybot does not work!!! I remeber i had a similar problem and I called Dell, and one of the techs helped me reinstall windows. but I did it just now and NOTHING HAPPENED!!! I iahce the Reinstallation CD service pack 2 cd...... SOMEONE HELP ME