mmm I personally use the mc command to launch Midnight Commander after SU (if installed ). If you want to edit any file in etc, just go to the RUN dialog and go into Options and check "Run as a different user" and enter root then below Password required enter your root's pass. And in the command field use the path to your favorite text editor ( I suppose writing kwrite or kate will do the job, but if the kde is not in your PATH, search for the kwrite executable, usually /usr/bin/kwrite or /opt/kde/bin/kwrite but I've got no Suse to tell you for sure).
When you launch the editor, open the file and have fun
I suppose your problem comes from the point that, you think that if you open the console and write su, you're root everywhere, but indeed it's only the console where you have the rights. Of course you can launch konqueror from within the console as root, or you can use the same way to launch konq with root rights, as you open the editor (see above). I suggest using the mc application, for me it does the work perfectly, without the need of opening konqueror. Just move to the etc dir, select the file and press F4, edit it and press F10 to save and F10 to quit again
Good luck!