The About menu is one of the first layer menu entries on the empeg. Press the Down button to get to the first layer, the left or right until you highlight the About entry, the Down to enter the About screen.

Just cause the cable worked for the previous owner doesn't mean he had the same [network] setup as you. If he connected through a hub/switch he most likely used a straight ethernet wire, but for a a direct computer to empeg connection you need a cross-over ethernet wire...