Since i'm guess you didnt like my answer from this morning i provide a bit
more info.
Windows XP doesnt include DOS, and if your hard drive is formatted in NTFS a
DOS boot disk will not even read the hard drive. you can boot from a DOS
floppy in order to format you hard drive or partition it, but these features
are built into the Windows XP CD-ROM.
If for some reason you should damage your install of Windows XP you can boot
from the CD-ROM and repair it from the Windows XP setup. You can also
access the recovery Console from the XP CD-ROM.
You can crate a "System Disk" if you are unable to boot XP, but the same
tools are on the Windows XP CD-ROM. An ERD disk like the ones you could
create in Win2K offers the same feautres the windows XP CD-ROM does.
How to Perform a Windows XP Repair Install
http://www.michaelstevenstech.com/XPrepairinstall.htm
Clean Install Windows XP
http://www.michaelstevenstech.com/cleanxpinstall.html
Windows XP Bootdisk Sets
http://www.bootdisk.com/bootdisk.htm
How to Use System Files to Create a Boot Disk to Guard Against Being Unable
to Start Windows XP
http://support.microsoft.com/?kbid=314079
Creating an Emergency Repair Disk (Win2K ONLY)
http://www.microsoft.com/WINDOWS2000/techenthusiast/tricks/administration/erd.asp