Make certain there are no spaces in the installation executable filename. (I renamed my download FirefoxSetup17_0_7esr.exe) It just doesn't like it!

I chose to modify the ini configuration settings found here: https://wiki.mozilla.org/Installer:Command_Line_Arguments and save the file as config17_0_7.ini .... This is the resulting batch (cmd) file uploaded & run through Kace:

 @echo off

REM========================================================================================
REM Install FireFox 17.0.7
REM========================================================================================

echo Installing Firefox - Please Wait.
echo Window will close after install is complete

REM Using configuration settings (in ini file) which installs program silently by default:
"***my absolute server path***\FirefoxSetup17_0_7esr.exe" /INI="***my absolute server path***\config17_0_7.ini"

exit 0

Modifying the Default Profile

Firefox saves its profiles in the user's %appdata% folder, so each user will have a new Firefox profile created for them.  To modify things like the default home page and bookmarks, you can create a folder at %FirefoxInstallDir%\defaults\profile.  See the link below for more information. http://mike.kaply.com/2012/03/30/customizing-firefox-default-profiles/

Note: The blog post mentions the omni.ja file; it shouldn't be necessary to modify this since creating the defaults\profile directory serves the same purpose.  This is a more preferred method of modifying defaults.

You can also actually repackage Firefox's setup.exe file to include the defaults\profile folder.  More information on that is here: http://mike.kaply.com/2012/02/14/customizing-the-firefox-installer-on-windows-2012/