How to save your data [duplicate]
You data will not automatically be saved but you can do something yourself. I don't know what your date refers to. If you want to keep things in your home directory, simply use a live CD or USB to preform the following command:
tar zxvf home_bk.tar.gz /home
and then use mv command to move it to a safe place and restore it after reinstalling the system.(this is actully working for any dicectory)
If your want to restore your settings, find the file and cp it to a safe place.Replace it after reinstalling.