Consider trying this (with 'System Preferences' not launched) -
01. Locate the file 'com.apple.print.FaxPrefs.plist' in the '/Library/Preferences/' folder, and trash and delete (empty the trash) the file.
02. Open 'System Preferences', select the 'Print & Fax' utility, and make some setting changes.
03. Quit 'System Preferences'.
04. Open 'System Preferences' and see if the 'Print & Fax' utility changes remained.