Hi k30ps and welcome:
I’m using Nero 8 Ultra but I think the following should be the same.
When you open Nero Burning Rom and are asked what file format you want to use, select “Cancel” (you don’t want any of those options (UDF, ISO, etc)).
After selecting cancel, under “Recorder”, select “Burn Image”. That will take you to the third screenshot. Select your iso image and burn it. It should work and remember to [B]only [/B]use Verbatim DL medfia as any other media is likely to give you headaches.
You have posted in the Nero forum and most members will respect that and not go off topic by suggesting other programs. However, I wish to point out that imgburn will allow you to control the layer break which is important to some members. Imgburn is free and has excellent guides. Regardless what you end up doing, the above screenshots (& only Verbatim for DL media) should get you going.