Dont use Internet Explorer, and get SpySweeper...
And use FireFox for the LOVE OF GOD!!
Download and Install FireFox and make it your default browser. DO NOT uninstall Internet Explorer, just neglect it and don't use it unless you have to, which is SO RARE.
Drop by BestBuy, we have SpySweeper on sale ALL THE TIME for $20! It gets rid of EVERY SCRAP of adware and spyware and popup strings!