NTDETECT.COM, BOOT.INI, and NTLDR on a floppy will create a boot disk that might be able to boot a XP installation with a bad or missing startup file, depending on what file is bad or missing.
But honestly that boot disk can't do anything you couldn't do with a XP installation disc.
But the important question here is what do you need a boot disk for? Because a boot disk can be many things.
(And please stop deleting your threads or I'm not going to bother answering any more of your questions. It makes helping you harder and makes it impossible for other people to learn from your questions.)