stuck in unix cmd prompt
I have a windows xp laptop that was accidentally started up with a linux (power cinema) cd in it. The computer asked if I wanted to run set up and I hit no, it then said 'hit return to activate this console', which I did. I now appear to be in a Unix cmd prompt. typing 'help' showed me some command options (break, cd .. return .. unset. etc). I've never worked in unix before and i can't get the computer out of it. I've tried typing exit, but it has no effect. The cd wont eject either (i've tried 'eject', 'eject cd' some similar combinations, and manual ejection). If I turn the computer off and then back on, the screen is exactly where I left off. I know windows is an inferior system and all but its not my computer and someone needs to be working on it.
I'm really in a tight spot and any help/advice anyone could give me would be greatly appreciated.
-thanks in advance