Interesting Problem with Layout

I have an interesting problem with my site, if I want any background color other than white.

http://www.john-neal.com

Now if you were to look at this page after that one

http://www.john-neal.com/pastWebsites/index.shtml

You can see that since the content is so short the background color is not stretching to the bottom of the page.

My right side menus when long like the pastWebsites Menu
if the browser window is too small the menu continues down past the bottom of the browser and the scroll bar does not appear.

I think both of my problems are related..

I need my middle content section to always stretch to bottom,
but if you look at my stylesheet you will see it is more complicated then the simple examples.

http://www.john-neal.com/style.css

I wanted to make the middle content a variable width and keep the left and right sidebars from floating over the middle.

With the nesting divs I have got the effect that i wanted.

I still have some bugs in this new design of mine.

I really would appreciate any help, I have been reading through all of the forum, and looking at all the suggested websites on stylesheets.

I have not been able to solve my problem.