I have also use Nero to make either an ISO or NRG and then edit with WinISO. My problem is making a bootable ISO > 2gb. Want to put more on my bootable AIO DVD, such as PartMagic, DriveImage, ERD Cmdr, XP, Office, FP, SAV, Nero -- which fit on 1.9gb -- and then add more like Server 2003, Office XP and 2003, etc.
What I have not done yet is to use Nero to make a boot DVD and use a boot file each time, just adding the changes to the compilation and burning each time instead of maintaining a large ( > 1.9gb ) ISO file.