Toshiba a200 recovery results in black screen

I am trying to reformat my toshiba a200 with the recovery disks. I turn on power, then hit f12 for boot menu, then enter cd/dvd (the first disk is in ). It says "windows is loading files" then the next thing should be "copying files". (I've done this before) But all I get is a black screen with a curser !! And when I try the repair it suggests on boot-up, all I get is a black screen again !! Can anyone help ??