There are 2 things to consider. First there is the specific settings for your user, and also system wide settings. As mentioned, all of your user settings exist in /home/user. If your system has space for it, you could create tar.bz2 backups of your entire home directory, and stick them somehwere else, either on a removable drive, or another location, like /var/backups or anything that suits your fancy.
It is also important on a system wide level to back up the /etc/ directory. That is where configuration for all users on the system are, and also the configs for things like ssh, samba, and nearly everything else reside. Just backing up your home directory is fine if your user account somehow gets screwed up, but if your system dies (hard drive failure, motherboard failure), having etc backed up will allow you to get the exact same system rebuilt very easily.
When I switched desktops about 9 months ago, I did a full tar.bz2 of my home directory, also one of /etc, and one of /usr/local where I compile from source, and using the dpkg tool in Debian, I was able to make a list of every program that I had installed. I installed the new system, used dpkg to reinstall all the same programs from the apt repositories, recompiled the things in /usr/local, replaced all the files in /etc with the ones from my old /etc, and untarred the home directory in the same place. I rebooted, and my new system was identical to my old.
There is also a great tool for making backups, called backuppc.
It really is excellent, and can backup other machines on your LAN as well, assuming you have the space to hold the backups. I don't know if Suse has that in its repositories, but I rather expect that it does. That makes backups easy to do.