Thanks for this, nelz
I had no problem using dvd2usb.sh to create a LXFDVD174.img file, which I did in Ubuntu 12.04 on my laptop (which does have an optical drive). After renaming the file to LXFDVD174.iso I tried running it in Ubuntu's VirtualBox. The LXF DVD menu appeared and I was able to select the various distros. I didn't take it any further than this as I am short of space on my laptop and the whole idea was to install Mint in VirtualBox on my Mac mini (if it was part of a Happy Meal I think I'd rather have a Mac maxi, thank you!). All I wanted to do was to test the iso file was working.
Unfortunately where I ran into trouble was trying to find a way to transfer that 4.4GB iso across to my Mac. I attempted it with a 16GB usb stick but the copying failed with “Error splicing file: File too large.” The stick is formatted msdos and I think there may be a limit on the size of file which can be handled.
So I gave up and simply downloaded the Mate version of Mint from the Mint website and I have installed that to my Mac mini's VirtualBox. I had been quite looking forward to the multi-desktop version and it would have been good if I could have simply created an iso for Mint alone (instead of the whole DVD) which would probably have fitted on my usb stick. But unless anyone can give me step-by-step instructions for doing this using mkisofs as Mike did for me
a few years ago for Fedora, that is a pleasure I shall have to forgo. I imagine the mkisofs command options, the significance of which I don't fully understand even though I have looked at the man page, must vary from distro to distro, and of course to start with you need to know which directories from the DVD to include.
Could this perhaps be a subject for a future tutorial in LXF? I'm sure I can't be the only one who would appreciate instruction in creating individual distro isos from the disc.