If you don't want gnome to run when you startx as root, edit your .xinitrc in root's home directory and enter the window manager you prefer. I'm guessing you would want KDE, which to get KDE, simply log in as root at the console and type:
# echo "startkde" > ~/.xinitrc
That line will add the line "startkde" to your .xinitrc file and from now on when you type startx as root, you will load KDE instead of gnome.
As far as anything better than XCDroast, I personally think it's one of the best CD burning programs available for linux. But then again I really haven't used anything else
You probably need to enable non-root-mode for XCDroast. To do so:
1) startx as root
2) load XCDroast
3) go into setup, and click on the users tab.
4) at the bottom click on the button for "Chang non-root configuration"
5) click on "enable non-root mode"
This will enable standard users to execute and use XCDroast.
Let me know how it works out,