Replacing a few files doesn't normally fix a corrupted file issue. Your best bet would be to reformat and reinstall the operating system plus SATA drivers on the drive that you want to use as the primary boot drive, in this case, the original hard drive. Unplug ALL other HD's when you do the reformat and reinstall.

Of course, since you already have a working operating system on a different HD, you might want to simply format the old drive and use it as storage.

Hope this helps.