The font for Icon descriptions, the Folder List and the Header pane window is the same as the Windows Icon font. From there, select Item and then Icon. At that point, the font readily can be changed.
Many users ask how to change fonts for sent messages.
The settings for these windows follow the Preview Pane settings noted below. The font in the message header pane of both Mail and News uses the standard Windows font. Please note if you change from one font to another and then click OK in the Fonts dialogue box, nothing may happen. In fact, even of you close and restart OE, the change may not apply. Once the file is open, find the font tag and change it to the font that you would prefer to use.