Connect the hard drive to the other IDE channel, get into BIOS(press Del or whatever key is specified on the BIOS screen at startup), and auto configure the hard drive. If it boots the system, then there's a problem with the 1st IDE channel's controller.
If the system does not boot, then make sure the HD's IDE cable is securely connected. If that's ok, try another cable. If still no luck, insert the Windows boot floppy, select 'Start Without CD-ROM Support' from the menu, press Enter, type dir x: (where x is your hard drive's letter) at the A:\> prompt. If you cannot see the contents of the drive, then it has died. You will need the assistance of a data recovery service and a lot of $ to retrieve your photos.
If you can see the hard drive's contents, then leave the boot disk inserted, restart, select the same start option as above, type c: and press Enter, type fdisk /mbr and press Enter, remove the boot disk and restart.
If this does not work, start with the boot disk inserted, select the same start option, type sys c: and press Enter, remove the boot disk and restart.