Selecting the ISO 9660 Format
To start an ISO 9660 disc:
1In the Data tab, click the Disc Settings button (or the disc title).
The Disc Settings drawer opens.
2 In the Disc Settings drawer, click Advanced, then select the ISO 9660 option.

See Also:

Overview of Making an ISO 9660 Cross-platform Disc
Adding Files to an ISO 9660 Disc