The highest priority should be to save the content of your [most important] personal files. For this purpose I think you should avoid writing anything to your drive.
My way to do it is to shutdown the computer and reboot from another drive (typically an Ubuntu live drive or a linux rescue system), and if you have valuable data in the drive, to clone it with
ddrescue to a third drive, and after that do recovery work on the cloned copy. This way you can afford mistakes (and in that case clone the drive again and try again to recover data from the cloned copy). The tools Testdisk and PhotoRec from http://cgsecurity.org might be useful.
This is described in some details in the following links,