Like http://www.linuxquestions.org/questi....php?p=5361621 but this time with ONLY linux distros

Do you plan to reformat the entire drive and reinstall completely new?

Back up the contents of your home directory, including any hidden files that you have modified. Which hidden files depends on what you have done. In my case, I would back up, for example, the .fluxbox directory, my Mutt configuration files, and so on, because I have extensively modified my Fluxbox configuration, as well as my LibreOffice template. Any hidden configuration files that you have left at default aren't worth backing up.

Also back up any files in /etc that you have modified. Again, in my case, this would be /etc/samba/smb.conf.

Back them up to external media or to shared directory on another computer. If that's not a possibility, you might invest in an external USB drive; they've become quite reasonable in price.

Install your new distro, make sure everything is updated and okay, then put the backed up files in place as needed.

A web search of "back up Linux for reinstall" will turn up a number of useful links.

I will keep my home partition to get files from the partition.(Its very big)