i think what you have to do is tinker with the folder options within a drive window. kinda weird how they are related. but try this:
-double click my computer
-click a drive (C or D or whatever you wish)
-then go to tools->folder options->view
-set your font to the way you want it
-then i think you just "apply to all folders"
that should hopefully fix things for ya. i think i recall having to do something similar to this when i would open a new window in IE and the darn thing would only open a tiny 2nd window. to remedy this, someone suggested to do what i mentioned and it worked.