I don't have the 2003 DVD so I cannot help you with that one. If you have the 2000.4.3A DVD for HP servers I can help you with installation. A lot more verification on the hardware is being done in 4.3A. These are just some of the items being inspected: Bios version and date, hard drive quantity and size, raid enabled within the BIOS, server model number, CPU speed, installed RAM, etc. Much more is involved in installing a copy as a clean install then versions 2.4, 2.7, etc. If you have an existing 2.7 installation you may be better off upgrading to 2000.4.3A (if possible).
I made a copy of my Cisco 2000.4.3A DVD and then had to replace the file osinst.vbs within the WINPE (preinstall) ramdisk ISO image with one that had the checking routines removed. Once this was done I burned the new ramdisk ISO image to the DVD and overwrote the previous copy. Like I say the procedure is fairly complex.
Take a look at the 2003.1.1 DVD and see if there is a folder on the DVD that contains .bin or .iso files. Let me know if there is such a thing on your DVD. The image file is extracted to your HD during the installation process.