An ISO file which is also known as the ISO image is an 'image' or 'archive file' of an optical disc in which the entire data content of the disc is represented. This ISO file can be burnt using Nero 8 ...

.nrg is the "proprietary" name for Nero image files. Just like .ccd is for CloneCD. If you had clicked on the .nrg file instead of renaming it, Nero would have opened up and burnt the image all ...