Adding Files to an ISO 9660 Disc
You can add files to an ISO 9660 disc in any of these ways:
With the ISO 9660 format displayed in the Data content area, select and drag files or folders from any location on your hard disk to the Data content area.
The files or folders you added appear in the Data content area.
With the ISO 9660 format displayed in the Data content area, click the Select button. The ISO 9660 window appears. You can drag files or add them to the Files tab using the Add button.
The files or folders you added appear in the Files tab of the ISO 9660 window. For more information, see Configuring an ISO 9660 Disc.

See Also:

Overview of Making an ISO 9660 Cross-platform Disc
Selecting the ISO 9660 Format
Configuring an ISO 9660 Disc