1.Please check this link to download Dos bootable files.
2.Use HP USB format tool to make your pendrive bootable.Format your pendrive with this utility.There is a Make DOS bootable option in that tool.
3.Locate dos bootable files.
4.Copy i386 folder from your windows xp installation disk to pendrive.
5.Make first bootable device to USB
6.Go to i386 folder and type winnt32.exe.Your setup will start now.