What directories do I need to save to backup my user settings?

Ok, so my disk is dying. I have read this - Best way to clone an installation (copying to identical hardware) - but don't really need to copy the whole partition. My data is safe.

1) What I need is to save my application/desktop settings for the user (I only have one - ME), and that of the system, since redoing the whole thing can become such a headache and I can't remember all of the modifications I've made.

2) Make an exact copy of all .deb files installed and mimic/download what is not there yet. Because the base install is gonna take care of it, I only have to download/upgrade the rest but not everything. This sounds a little vague. It will only copy the info of what .deb files were installed not the actual .deb files

Is there an app like this? Thanks!

1. It'd be a good idea to just copy all of /home as that contains your documents and preferences. If you just want to know where preferences are stored, it varies. Many applications store them in .config (that's /home/username/.config) and .local. Most user preferences will be in .gconf. Some older applications might save settings in .gnome2. Firefox uses .mozilla; other browsers use .config as far as I know. To be safe, I'd just recommend backing up /home still.

2. Run dpkg --get-selections > ~/my-packages.txt to build up a list of everything installed (or removed) on your system. It will be saved in your home folder as my-packages.txt. Once you reinstall, run sudo dpkg --set-selections < ~/my-packages.txt (assuming the file is placed in the same location again) and then sudo apt-get -u dselect-upgrade to start installing packages. You'll want to also back up /etc/apt/ and restore it on the new installation to ensure that any extra software you may have installed is still able to be installed again.

It sounds complicated (and boy does this post look weird with this formatting) but it's not too awful considering the alternative of installing everything by hand again.

If you prefer a GUI Luckybackup is a cinch - available in the Software Centre, even so I tripped over the instructions at first, but its a very flexible.

I have it set to backup Home weekly. Good stuff. It restores too of course.