TestDisk is a great tool for recovering files from a broken disk. My wife's hard drive crashed yesterday and it turned out to be a corrupt boot sector. I booted to a Kubuntu Live USB and was able to use TestDisk to recover the MBR from the backup (it was NTFS which keeps a backup at a different part of the drive) and copy the files I needed to a USB key.

It has a command line interface, but you simply run "sudo testdisk" and there is a guided menu based approach after that.

If you are having any hard drive issues it's a good first place to start.