Hello Peter, Welcome to the best Windows forum out there!
Let me guess: you did a full backup with Nero, and not just specific files and folders? If so, then you cannot just restore it to your new machine.
Is the old HD still intact, or did you install Windows 7 on top of it? If it is still untouched, it might be easier to just plug in the old drive to the new system and transfer the data manually.
If you installed on top of it, try using reocvery software to recover the deleted files, provided you did not format the drive. I suggest Recuva
Hope this helps,