After Firefox has finished importing your Microsoft Internet Explorer settings, you'll see a pop-up window that will ask you if you want to make Firefox your default browser. You can do this now or later. Sometimes, if you've been using IE for a long time, it can be difficult to get used to the look and feel of Firefox all at once, so I suggest that you keep IE as your default browser until you get more comfortable with Firefox. Once you learn how much Firefox can help in your searching, however, you'll want to make it your default.
Whatever you choose, Firefox will finally open to the Firefox/Mozilla main page. This is the default page that (for now) your browser will open to. If you want it to open to something other than this, navigate to Tools, Options. At the top of the window will be an area marked "Home Page Location." Input whatever you'd like that to be (see How to Set Your Home Page for more information) and press OK. You're all set!