I think you can try Recuva if you are looking for a freeware. Expect this, all are commercialware and you need to buy them. But before getting any recovery tool, either freeware or commercialware, you must find out the reasons which cause corruption in system hard disk drive. There are many causes which can corrupt or damage your hard drive. I would like to share a blog here in which you'll read about all the possible causes behind corruption or damage in system hard drive. You'll also read how to avoid these causes to corrupt or damage our system hard drive.

Hard Disk Drive Failure: Symptoms and Causes

Read this blog. Hope this would be helpful. Once your doubts are cleared (regarding for corruption in hard drive), you can try Recuva or any other tool. But first try to get their trial or demo version.