What do you mean XP bootable CD? If I am not wrong, every XP CD is bootable. All you need is setup your CMOS to boot your computer from the CDROM.
Incase if you XP CD is not bootable, I am sure it is a pirated software. Well buddy, if it is just a setup copy, there can be a possiblity that more files would be missing. So why take chances with your OS. Get a full bootable XP CD, pirated or original depends on you...