An iso file is an Image of the CD or DVD it was made from. So if the source was bootable so should the CD/DVD made from the iso file. Additionally sicne the file is an image there should not be any need to extract the files from it to burn it.
Your burning software should have an option to create a CD/DVD from "image". From there point the software to the iso file and let it burn. It should recreate the CD, and make it bootable.
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Ignorance is not necessarily Bliss, case in point:
Unknown has caused an Unknown Error on Unknown and must be shutdown to prevent damage to Unknown.