Simple html and java script navigatation

Hi all,

I have this very simple question about html and java script navigation.
Please see mock up images at http://www.dreamance.com/download/example.jpg

It a very simple site with top as navi and bottom content. The client want to do it in the way that he only need to update the navi section once and all other page with the navi section will be updated. The solution I can think of is using a different frame both the navi and content (or is there other solution?)

However, the is sub section when u roll over a button (see button 2). The sub section drop down must be able to bleed to the bottom content page, else I cant be see.

Is there any solution you guy can suggest to me?

Thanks