dvd+rw-mediainfo /dev/sr0 | grep "Write speed"
cdrecord -prcap dev=/dev/sr0 | grep "Write speed"
mkisofs -o my_disc.iso -udf -iso-level 3 -J -R -V "REPLACE-DISC-LABEL" /path/to/files
(Use -iso-level 3
to allow files larger than 2 GiB to be included in the ISO.)