Debian didn't boot from CD

[Christian Imhorst <christian.imhorst@gmx.net>]

Hallo,
I've the Toshiba Tecra 8000 with CD-Rom but without a Floppy. The
Bootsequenze is, that the Laptop first boot from CD and than from the Hard
Disk. I'm able to install SuSE Linux from CD and to boot the Knoppix-CD,
but none of my Debian CDs. I've taken "potato" and "woody", but none of
them show me an installation screen. And it doesn't matter, if the SuSE,
Knoppix or Debian CDs were bought, from a handbook or self-burned. Why
didn't the Debian-CDs want to be installed?

Regards,
Christian.