Internet Hooks

I’ve been hooked by some unscrupilous internet site and now when I connect to my Internet Explorer I am dillused with pop-up windows wanting me to download software and signup to what I believe to be X-Rated sites. I found a part of the problem in my Home page setting. If I go to IE’s Tools;Internet Options;Home Page, the text in that window is greyed and I can’t change it. I have upgraded my IE from rev. 5 to rev. 6 in an attempt to correct the problem but it still is there. How do I correct this ?