1. Use
cdrecord --scanbus to find your device id. Then make sure you have the line:
Code:
/dev/scd? /cdrw iso9660 defaults,ro,user,noexec,noauto 0 0
In your fstab replace the ? with the id number. I created the /cdrw directory with mkdir in / for the mount point. You should be able to burn with K3b with the defaults included at least that's how it worked for me.
2. What error are you getting. I had to update two lines the
/etc/apt/sources.list in the XFree section that was pointing to the wrong directory (it was moved) this may be the problem. If it is not then post the output of the error.