Making Bootable OS Disc For Mountain Lion - What AM I Doing Wrong?

Question

So here's my delema, I have purchased the Apple Mountain Lion Application (.dmg), and want to make a bootable DVD as a backup for possible re-installation. I know there is the "Recovery OS" option on my new 21.5" iMac ... but I still like to have a bootable disc as backup.
After burning the Mountain Lion .dmg, called "InstallESD.dmg" to a standard DVD .... and starting up the iMac (holding down the "option" and "C" key on the keyboard during start-up .... all I was presented with was the start-up screen showing the iMac Hard Drive icon or the iMac "Recovery" icon .... and NO BOOTABLE DISC, as a third option.
So what am I doing wrong?  I have this same basic problem creating "bootable" start-up discs for my "DiskWarrior", "Data Rescue", and other software that I would like to have the option to boot off a physical disc.  I know there is a way to make USB flash drive bootable drives, but again, I'd like to be able to run these "bootable" programs off a burned disc as well.
Here's what I first did:
1. Got the original Apple Mountain Lion "InstallESD.dmg"
2.  Originally made and burned the Apple "InstallESD.dmg" on DVD, and got this:
   With the following burned contents below:
   Of course, launching this as a "bootable" disc did not work
So what what is the proper way to get the "InstallESD.dmg" installed so it opens up
upon Mac start-up along with the other start-up Hard Drive grey screen options?
This is what is available for content on the "InstallESD.dmg".   Should any of this be
burned separately on the "Bootable" DVD, instead of the closed "InstallESD.dmg"?
Exactly what should be opened and burned onto a DVD to get the Mac to
recognize the "bootable" DVD contents .... and to show up as a "launchable" option
along with the standard Mac grey screen start-up icons?
Also, exactly what keyboard keys should be used to launch a "bootable" disc
on start-up?  It always used to be "Option" + "C" key .... has this changed in
Mountain Lion?
Any assistance will be appreciated.
Thanks

Answer 1

You can't use that setup to burn a bootable DVD because a DVD is not writeable once created. Use, instead, an 8 GB USB flash drive:
Make Your Own Mountain/Lion Installer
1. After downloading Mountain/Lion you must first save the Install Mac OS X Mountain/
    Lion application. After Mountain/Lion downloads DO NOT click on the Install button.
    Go to your Applications folder and make a copy of the Mountain/Lion installer. Move
    the copy into your Downloads folder. Now you can click on the Install button. You
    must do this because the installer deletes itself automatically when it finishes
    installing.
2. Get a USB flash drive that is at least 8 GBs. Prep this flash drive as follows:
  a. Open Disk Utility in your Utilities folder.
  b. After DU loads select your flash drive (this is the entry with the mfgr.'s ID and size) from the left
      side list. Click on the Partition tab in the DU main window.
  c. Under the Volume Scheme heading set the number of partitions from the drop down menu to one.     
      Set the format type to Mac OS Extended (Journaled.) Click on the Options button, set the
      partition scheme to GUID then click on the OK button. Click on the Partition button and wait until
      the process has completed.
  d. Select the volume you just created (this is the sub-entry under the drive entry) from the left side
      list. Click on the Erase tab in the DU main window.
  e. Set the format type to Mac OS Extended (Journaled.) Click on the Options button, check the
      button for Zero Data and click on OK to return to the Erase window.
  f. Click on the Erase button. The format process can take up to an hour depending upon the flash
     drive size.
3. Locate the saved Mountain/Lion installer in your Downloads folder. CTRL- or RIGHT-click on the installer and select Show Package Contents from the contextual menu. Double-click on the Contents folder to open it. Double-click on the SharedSupport folder. In this folder you will see a disc image named InstallESD.dmg.
4. Plug in your freshly prepared USB flash drive. You are going to clone the content of the InstallESD.dmg disc image to the flash drive as follows:
  a. Double-click on the InstallESD.dmg file to mount it on your Desktop.
  b. Open Disk Utility.
  c. Select the USB flash drive from the left side list.
  d. Click on the Restore tab in the DU main window.
  e. Select the USB flash drive volume from the left side list and drag it to the Destination entry field.
  f. Drag the mounted disc icon from the Desktop into the Source entry field.
  g. Double-check you got it right, then click on the Restore button.
When the clone is completed you have a fully bootable installer that you can use without having to re-download Mountain/Lion.
Note: The term Mountain/Lion used above means Lion or Mountain Lion.