Ide or atapi 0 drive 0 (or master)
What motherboard do you have?
Bios looks something like this: http://media.photobucket.com/image/boot%20drive%20detected/Mington/BIOS_NoDrives/2.png
Boot looks like this:http://www.bahj.com/wisp/instructions/screenshots/booting/bios-boot-menu-message.png
Ignore the circled f11 thing... you should see your drive listed in the ide section. If its not listed there then the mobo doesn't see it and therefor windows never will. I only show the IDE because I dont think there are any sata cd rom drives.
If its not listed there, then we may have to "Turn on" the ide interface which varies depending on your motherboard.