To change your homepage in Internet Explorer, once the preferences opens up, click on the triangle next to WEB BROWSER. It should expand the list of options to what you see on the left.

Once that's up, in the middle section you'll see the "Home Page" area. Delete whatever is in the "Address:" field and you can then type in the address you would like to use for your new homepage.

Hit OK and then next time you hit the HOME button or re-open Internet Explorer it will load up your new homepage.
Click here to return to the Mac Internet Explorer menu