The SSRMS is really meant to controlled by an actual controller like the keyboard or an actual joystick just like the real thing. Controlling it through a dialog with buttons like that is considered a back-up contingency mode called "Single Joint Drive" and is really only meant to drive the arm to a safe position where it is out of the way and can be troubleshooted easily.
The "frame mode" is where the reference frame is calculated from, either the shoulder joint where the two arm ends connect or the base End Effector (EE). I would personally train on using the shuttle RMS until you're familiar with it and can grapple things and move them around smoothly. SSV has a similar SRMS implementation to the SSRMS so it's a perfect training tool.
