To access the main menu, hold down the control key anc click the left mouse button
control-middle button is the terminal options (Preferences)
control-right button is the font options

To Scroll using the scrollbar, grab the grey bar with the middle button

Startup Options

Start Xterm as a login shell (load /etc/profile and .bashrc (on redhat, at least))

xterm -l

put the scrolbar on the right side of the term

xterm -rightbar

Use a visual Bell (screen flash) instead of a beep

xterm -vb

Change colours

xterm -fg <foreground colour> -bg <background colour>

Swap forground/background colours

xterm -rv

running a program in Xterm

xterm -e <program name>

For more information see xterm(1)