Format CD from command line?

Hey, I'm getting ready to reinstall the OS on my mom's old xp. Trying to copy stuff that she wants to keep to a cd but I can't figure out how to format the drive. Right clicking on the drive letter doesn't bring up the format option. I know it works, because I did one cd, but now I can't. Was wondering if it could be done from the command line.

Any help you can offer will be greatly appreciated.

TIA