While editing a Word 2010 document which contains multiple types of text styles and formatting, it is quite bothersome to select text each time and then choose the default Font settings from Font group under Home tab. You can use a simple combination Ctrl +Shift+N to change the font settings immediately to default settings.
When combination is used, it will switch to default Font settings (Word 2010: Font Family Calibri and Font Size: 11).
Under Font group, there is an option for changing the default font settings. Just select the default font style, format, family and size, and use the combination to revert back to default font.