yea, depending on what version of Nero (version 5 or 6 - these instructions will not work with Nero Express), you may need to modify the instructions slightly..
1)Cancel the Nero wizard so you have the main Nero Burning Rom open with no compilations
2)Click File > Burn Image
you may need to change the "Files of Type" selector to include "ISO" files or seletct "All Files"
3)Select file
4)Burn