"It can be done. I use RIP linux as the host system because that has a grub patch which allows one to have a grub menu on the cdrom. To see how the entries in the grub menu should look for each distro, look in the file called isolinux.cfg .
I also have a bunch of extra tools in the images directory. Instead of putting every one of these in the menu, I can just edit the boot entry. It helps if you know how to edit the grub menu at boot up time."
http://www.linuxquestions.org/questions/linux-general-1/several-distro-in-one-cd..-224186/
