My website Cool As Fire the site displays differently on every browser.

This is very inconvienient when im trying to build a website.

Here is what the same page looks like in 3 different browsers:

IE:
http://www.martyn.x3hosting.info/ie.JPG

Firefox:
http://www.martyn.x3hosting.info/firefox.JPG

Opera:
http://www.martyn.x3hosting.info/opera.JPG

As you can see they are all different, I want it to look like the Firefox one, but for some reason it looks different in each.

Can anyone help or have any recomendations? (it will be greatly appreciated).

Thanks!