Hi all
Wow, a topic I can contribute to!
Basically, Disk Utility in OS X El Capitan has been "broken" in as much as all the slightly more power-user stuff, like creating bootable DVDs, has been taken away. I have a stack of drinks coasters from the last week or so to prove it.
I even went on to a support chat with an Apple Engineer and we got down to having to use the command line to burn images. I was burning an image downloaded from here that said it was bootable, but OS X El Capitan just wouldn't burn it this way, until after about 60 mins the best the engineer could come up with was "that image can't be bootable".
I've now got a PB G4 with OS X 10.3 that I'm going to use to burn another. I think it's disk utility is full functional.
Thanks
Stuart