If HD is seen in BIOS, run maker's HD Diagnostic
extended CD scan to see if it can be repaired. It might regain enough functionality to copy your files out: Copy & Paste - in Windows Recovery Console
If it is not seen, you can boot free Partition Wizard
bootable CD to see if it sees the HD, run a File System Check if so to see if it will respond. If not and it is seen by PW, there are other steps here to try when Windows 7 fails to boot
so that you know everything possible has been done. I would run the Partition Recovery Wizard if any are missing on PW map.
If it's not possible to recover the old HD, you can use PW CD to shrink the larger HD from the left by enough to reinstall Windows 7 there. You can then transfer data into the User folders while using PW to Resize the data partition smaller and the Windows 7 partition larger, or just link the data from it's partition to a Windows 7 Library - Include a Folder - Windows 7 Forums