If you have the content DVD as .iso you can use Toast to mount it.
Or you can burn it using hdiutil from the Terminal. Just type
hdiutil burn
and then drag the .iso file into the Terminal window.
Should look like this:
$ hdiutil burn whatever.iso
Toast burns iso as well, but I've had problems in the past with obscure formats like
those for old EMU samplers. hdiutil always worked.