Raspberry Pi Start Up Issue

Installed the Openmediavault flavor of OS and fired it up. It comes up to a command-line prompt sign in, only accepts pi / openmediavault to get you to the pi@raspberrypi ~$ prompt. From there I am stuck, startx doe not work. Even changed to SU root@raspberrypi:/home/pi# prompt and still startx doesn't work. Would be grateful for any assistance.