in the toolbar click the left-most button (Creates a new compilation)
or File -> New or Ctrl-N
in the left pull-down menu select DVD.
in the scrollable icon list below that choose DVD-ROM (ISO), DVD-ROM (UDF) or DVD-ROM (UDF/ISO). the last option is the most preferable.
in the Multisession tab select No Multisession.
you can choose a few more options in the other tabs.
in the ISO tab i recommend:
File System: ISO9660 + Joliet
File name length: Level 2
Character set: ISO9660.
in the UDF tab i don't know what's options are best for highest compatibility...
One Ring to rule them all, One Ring to find them,
One Ring to bring them all and in the darkness bind them
In the land of Mordor, where the Shadows lie
M.C. Escher - Reptilien