In Windows, you have apparently selected "fax" as your default
printer in Start | Control Panel | Printers. In Word, if you
click on the Print button on the Standard toolbar, then the print
job automatically goes to the currently selected or default
printer. In Word, if you press Ctrl+P or click on File | Print,
you can choose which printer to print to. See
http://www.gmayor.com/fax_from_word.htm for an alternative solution.