If Ghost had been used to burn the image to optical media directly, then Ghost would recognize and mount the image directly without needing the DOS drivers mentioned above. You do not say, but I'm guessing you are using Ghost 2002 or 2003, you created the image to HDD initially, and later burned it to optical media with a third party burning program.
Symantec's Ghost, for unknown reasons and poor documentation regarding functionality, will not mount a Ghost image on optical media unless Ghost was used to actually burn the image to the media in the first place-unless you use the DOS drivers that mount the optical drive from *config.sys* (example-oakcdrom.sys), and assign drive letters from *autoexec.bat* (example-mscdex.exe).
*No*-probably not either-but there probably is a simple solution. Am I just being stupid and missing something really simple?