How to boot using recovery disk

I want to boot my system using my recovery disk.  I have Windows XP, when I go to restart and get to the boot menu, I can't  get it to read from the CD before Windows launches.  I have been able to get  into the menu that allows me to change what the system boots from but I can't change it to the CD b/c my keyboard does not work in that mode for some reason..What am I doing wrong?