The people who did the fix said that I could selectively copy stuff that mattered to me
I should ask the people that did the fix for you where they got the Operating System from.
If they had used a standard back-up procedure, assuming right back to an install, then it would have prepared the disc as it was as new. Sadly, this means that it F-discs the the HD and puts a partition in ready to put your Restore information in.
Since the disc can't wipe itself and then carry on reinstalling, I would guess they had to have either your Restore disc on a CD, or they used an OS that is not kosher.
First check. Have you got a drive D:? If so, what size is it and is there anything in it?
FS and HP seem to used the same as most suppliers.