sub menu's not working when site adapted to 480ox

I am trying to make my website responsive, adaptive or whatever and am testing it at 480px in opera 7.
I have come across 2 problems;

1. The sub menu in the nav bar is disabled
2. The nav bar flows outside of it's frame.

Is there a way to prevent the sub menus from being disabled (the nav bar is in css) and the nav bar from overflowing?

I have thought of using a drop down menu or putting the sub menu's on the page where the text boxes are that sub menu links to. Is there a best practise for this?

You can see the css code here

I have attached a copy of the url as seen in opera 7 on a mobile.

Is there a way to get the picture to reduce in height? If not I can make a smaller image.Attachment 15083