As mentioned in ManEons, menu files are designated as .rgy files. In reality these are just text files that can be edited using a native Windows text editor like Notepad.exe. The formats for a terminal's main menu and a terminal's manditory menu are exactly the same. You can modify the characteristics of any connection just by modifying the text in the .rgy file, saving it and then sending (push out or upload) the file to the desired terminal as described in the ManEons article.
Below is a description of the menu for a typical Eon terminal in the student lab MC 2061. Below that is the contents of the corresponding .rgy file (menu_mc2061_cs_teachlab_term.rgy) which dictates the configuration of each connection for such terminals.
[Connection/Netscape/How Do I Use This Terminal] autorestart="false" autostart="false" enableAltKeyAndRightMouseBtn="false" enableLogoButton="false" enableStatusBar="false" kioskMode="true" preferences="" preserveCertificates="false" preserveRegistry="false" preserveSignedapplet="false" showBackButton="false" showBookmarks="false" showForwardButton="false" showHomeButton="false" showLocation="false" showMenuBar="false" showMyNetscapeButton="false" showNavigationToolbar="false" showPersonalToolbar="false" showPrintButton="false" showReloadButton="true" showSearchButton="false" showSecurityButton="false" showShopButton="false" showStopButton="false" startPage="http://www.cs.uwaterloo.ca/cscf/howto/thin/eon_guide.html" preserveSecmodule="false" [Connection/RDP/elegans.student.cs (CS Teaching Windows Front End)] application="" autorestart="false" autostart="false" clientname="" directory="" domain="" enableEncryption="true" enableMouseMotion="true" layout="Local Keyboard" password="" resolution="Full Screen" server="elegans.student.cs.uwaterloo.ca" usePixmap="false" username="" desktop="true" [Connection/XDM/fe10.student.cs (CS Teaching Solaris Front End)] accessControl="false" autorestart="false" autostart="false" ConnectPriority="disconnect" emulation3B="true" fontPath="/usr/X11R6/lib/X11/fonts/misc/,/usr/X11R6/lib/X11/fonts/75dpi/,/usr/X11R6/lib/X11/fonts/100dpi/,/usr/X11R6/lib/X11/fonts/tn.full/,/usr/X11R6/lib/X11/fonts/Type1,/software/font/data/x11,/software/x11/data/font" fontServer="fonts1.cs.uwaterloo.ca" fontServerPort="7100" host="fe10.student.cs.uwaterloo.ca" keyAutorepeat="true" lastConnXdmhost="" mode="Direct" numLock="false" Password="" ptrAccelDenominator="1" ptrAccelNumerator="2" ptrAccelThresh="6" QueryDialog="true" QueryTimeout="10" RemoteManagerOverride="false" saverBlankTimeout="10" saverDPMS="true" saverEnable="true" saverOffTimeout="40" saverStandbyTimeout="20" saverSuspendTimeout="30" scrnDepth="16" scrnResolution="800x600-60" serverTimeout="30" useDesktopDisplay="true" useDesktopFonts="false" useDesktopMouse="true" useDesktopScrnSaver="true" useDesktopVNC="true" QueryAccept="false"