When you are in a remote desktop window the keyboards shortcuts you have become familiar with change slightly. Here are a few of the more common ones:

ALT+PAGE UP – Switches between programs from left to right.
CTRL+ESC – Switches the client between a window and full screen.
ALT+HOME – Displays the Start menu.
CTRL+ALT+MINUS (–) – Places a snapshot of the active window in the Remote Desktop session on the clipboard.
CTRL+ALT+PLUS (+) – Places a snapshot of the entire Remote Desktop session window on the clipboard.
CTRL+ALT+END – Displays the Task Manager