Boot from CD message not appearing

I have followed the steps for creating a Symantec Recovery Disk as outlined on this site (http://us.norton.com/support/kb/web_view.jsp?wv_type=public_web&docurl=20091016094409EN&pvid=nghost_15&selected_nav=5). I had no problems going into the BIOS, then to the Boot menu, then moving down to option to select the CD drive where the recovery disk sits ready to go. However, when I reboot, I never get the message "press any key to boot from CD." The only system message I get is the brief appearance of the black-and-white screen that gives me my option to go into the Windows Recovery Console, which has been installed for some time.

 

What might be the reason I'm not getting the opportunity to bood from the recovery disk CD?

 

(If it matters, I'm running Windows XP Pro SP3 with all updates and regular use of the Disk Cleanup and Disk Defrag utilities.)