Black screen, blinking cursor

I downloaded the rescue disk iso, burned it to disk and booted from it. After a lot of messages in a large font and a lot more in a small font it stopped with a black screen and a blinking cursor. I assume it’s waiting for something but I don’t know what.
The machine is 32bit, runs under Windows 7 and is completely offline, ie it has no network card.
Does this not work without internet access (for access to definitions perhaps) or am I missing something?
Many thanks.