How to write ubuntu (iso) and super grub disk(iso) on one DVD?
I want to boot them.
This is theoretically impossible - an ISO file represents the phyisical layout of the filesystem exactly as it would be written to disk. Therefore two ISO files could easily contain two different filesystems - how would an ISO image burner "merge" the two incompatible filesystems?
Even if the filesystems in the two ISO files were identical, don't forget that an ISO file can contain a boot image as well. How could two boot images be merged?
Instead, you could try opening the ISO file with archivemount :
Those two commands will mount the archive and open it in Nautilus (or your default file manager). You can then begin copying files out of the archive to another location.
Grub can be written to a CD. You might be able to figure out how to create a bootable CD that contains the contents of both ISO files and can boot either image.