Please see this

I am pretty new to CSS, and trying to build a layout without using tables.
I basically want one header (fixed size) two fixed sized frames (left and right), and a dynamic-size content center area.
I have found some tutorials but couldn't achieve the effects i want. On this page (as well as on tutorials examples), everything is just fine as far as browser window is big enough.

What i want is that as the browser window gets smaller, the center part gets smaller as well up to a certain point.
Once let's say the center is 400 pix large, i'd like it not to resize anymore, and the browser scrollbar to appear.
Also i want the right frame to always stay on the right of the center part whatever happens (i have achieved that nesting the frame).

To prevent the center part from becoming smaller than a certain size, i tried using the min-width attribute, but it didn't help at all (the center still becoming smaller than that size). Anyone has a clue on using that attribute ?

I used a trick to solve this problem, i.e. having an image of the center size i want put in there and made invisible (not in my example to make it understandable). as seen in the example, this prevents the center part from getting smaller and makes the scrollbar appear.

Now there are two problems left :

1) the center part doesn't get smaller, but the text still moves. What i'd like is something like what can be seen for example here, done with tables, the center content area resizes up to a certain point and then becomes scrollable including the text.

2) if you make the browser window really tiny, and then scroll to the right, the top frame is cut !?!?

Thanks for reading and thanks even more for anyone with a solution.