You can control lots of things about the menu structure. I would start with the article Menu Structure and Properties, and also read the rest of the articles related to the menu, and you should be able to figure out how to do what you want.
You can even use a different skin on the home page than on the rest of the pages in your site if you need to. You can enable per page skins from site settings then you can choose the skin for any page from page settings.
Hope that helps,
Joe