Especially for a presentation, it is often useful to change the editor's font size. By pressing the CTRL-Key while turning the mouse-wheel, an editor's font is quickly changed.

A concrete font can be choosen bz the font selection dialog, which is accessable vie the pop-up-menu:

"More" - "More" - "Font"
The default font for new windows is specified in the Launcher's settings dialog:
"System" - "Settings" - "View-Style" - "Fonts"