Hi,
Does'nt those computers have 12 inch screens? And the possibility for a very high resolution? Together that give very small graphic in generel.
You could use Windows magnifying function while you change the Audio and Midi settings.
Or you could change your screen resolution. Just keep in mind, that that might rearrange your Windows desktop.
AFAIK you can't resize the Audio and Midi settings window. It would make it very big or very small in other situations, so it would be useless.