Why SuperGrubDisk won't boot up anything?

"What version of SGD are you using? I just tried v. 1.21 from here and for me it works without any problem. The screenshot I get looks like this:

The only thing that surprised me about your question is that you managed to burn a CD iso onto a DVD... I did not know it was possible (but I am not suggesting you are wrong here!). Do you obtain the same results by booting from a USB stick?"