I have tried to burn cds in both K3B and Gnomebaker, and I can only burn them as su. DVD burning works under the user account, however. Just thought I'd let you know.
Update: I fixed it through the magic of Google.
just put this in the /etc/rc.local file.
chown root:cdrom /dev/sg0
after a reboot everything works like it should. Since the rc.local runs at startup