So you have made an image copy of your OS cd or dvd? Now, how can I make the Nero .nrg image file to show up in VMware? VMware only can list iso format files?

If you are using image files to setup your VMs in Vmware. You will need to change your .nrg file to .iso file.

There are software that can convert .nrg file to .iso for you. e.g. MagicISO

But for us in this case, renaming the file to .iso works just fine. VMware was able to read the image OS file.