I believe .NET 3.0 provides a neat way to do this.  In 2.0 and below, the
only way I've ever done it has been to handle the Resize event and compute
new sizes for everything.

A suggestion:

You are misusing the term "aspect ratio", which describes the ratio  
between the width and the height, using it instead to simply describe  
scaling of the window.

It is true that if you can accomplish the scaling, you will also likely  
want to control the aspect ratio.  But it appears from your question that  
your primary concern is to control the scaling.

You will get better responses if you use the right terminology in your  
question, since if you are using the wrong terminology, some people who  
might know the answer to your question may just skip over your post  
thinking they don't.

As far as your specific question goes, I don't know the answer off the top  
of my head.  You can accomplish _part_ of what you're asking about by  
using the various the anchoring properties in the controls on your form.  
I suppose you could combine that with some code in the Resize event that  
changes the font size for the form as a function of the size relative to  
the original size, but I've never tried this myself.  My recollection is  
that you can have the child controls inherit the parent's font, but if I'm  
wrong about that you can easily enumerate all the children and set their  
font explicitly.

And as I alluded to, if you do all that you may also want to include code  
in the Resize event that restricts the new size to one with an aspect  
ratio that is identical to the original aspect ratio.

Pete

Thank you all for your replies.  

Yes, "Scaling / Aspect Ration" I think is what I was trying to ask about.  
Anyway, it seems easier (for now) to do what I have been doing - having 2
different sizes of the same app.  The only hassel is that whatever I do to
one app I have to do to the other app.

I guess I will do the lazy thing and wait for .Net 3.0 to come out in full
bloom.  Will VS2005 work with .Net 3.0?