MSTSC / RDP Shortcut Keys

Here's the full list of RDP/MSTSC shortcut hot keys for future reference

ALT+PAGE UP
Switches between programs from left to right.

ALT+PAGE DOWN
Switches between programs for right to left.

ALT+INSERT
Cycles through the programs in the order they were started.

ALT+HOME
Displays the Start menu.

CTRL+ALT+BREAK
Switches the client between full-screen mode and window mode.

CTRL+ALT+END
Brings up the Windows Security dialog box.

ALT+DELETE
Displays the Windows menu.

CTRL+ALT+MINUS SIGN (-)
Places a snapshot of the active window, within the client, on the Remote Desktop Session Host (RD Session Host) server clipboard (provides the same functionality as pressing ALT+PRINT SCREEN on the local computer).

CTRL+ALT+PLUS SIGN (+)
Places a snapshot of the entire client windows area on the RD Session Host server clipboard (provides the same functionality as pressing PRINT SCREEN on the local computer).

Remote Into a VirtualBox Appliance

The "magic sauce" is to remote into a headless appliance that way your remote session will automatically re-size. If you launch the appliance with VirtualBox locally and then remote into you cannot re-size it.

The alternative is to use VBoxHeadless directly, as follows:
C:\Program Files\Oracle\VirtualBox\VBoxHeadless.exe --startvm "Image Name"

Trouble Shooting

Make sure to turn off 3D video acceleration, it was causing a window to appear on my Windows 7 host, and it interfered with the remote connection.

Had trouble connected to my VM on my LAN, there were multiple Firewall rules with Windows 7.  Ended up deleting all of the rules for both Virtual Box and Headless, and when things started again, it allowed access.  That fixed the problem.