Hi,
I'll start with options that you have and then ask some questions regarding your post that are not clear to me.
Firstly - your best option would be to either use floppy or PXE booting. Floppy would be more preferable in your mobile case.
1. Create simple ghost floppy boot disk with network support.
2. Burn gho image together with ghostcast exe onto a DVD. From memory ghostcast exe is completely standalone app and you can run it pretty much from anywhere.
3. Startup ghostcast exe, point it to your gho image on DVD and start the restore session.
4. Boot client machine from floppy, connect to your ghostcast session and restore your image.
Similar story goes for PXE booting but it may not suit your moving environment as much. Hopefully this is what you need.
Now back to your original question that I want to ask few more questions to better understand your problem.
1. You are saying that you gho to DVD and "someone" tells you that disk was not created with symantec ghost, who's that? Ghost exe or ghostcast exe or someone else?
2. Also what do you mean by "ghost cast startup disk"? Is it just floppy disk created by ghost boot wizard or something else?
Thanks!