ISO files - Can you drop them into TMPGenc DVD Author for reauthoring?

[ibzomie]

I seem to remember a while back dropping an ISO file into DVD Author and then reauthoring it. However, I now have several ISO files that I would like to reauthor (some because they are too large for one disc, and some because I don't like the way the chapters are set up), and when I try to drop any of them into DVD Author, I get a message saying that it is an illegal video file, and that I must use MPEG1 or MPEG2.

I know that the file must be MPEG1 or 2, but, like I said above, I seem to remember doing this in the past. I thought that an ISO file is basically an MPEG2 but with a different name (I know it's probably not actually that simple). Are there different kinds of ISO files?

I also tried one of these files in DVD Shrink, (because it's too big to fit on one disc), and Shrink wouldn't accept it either.

They also seem to play just fine when opened with VLC Player.

So, my question is, How do I get these ISO files into DVD Author for reauthoring, or into Shrink to make them smaller?

[roma_turok]

Load ISO image to Daemon Tools virtual CD/DVD-ROM emulator.
Import as DVD VIDEO to TMPGenc DVD Author for reauthoring.

[Alex_ander]

Unpack with WinRAR trial, then open VIDEO_TS folder and drag/drop VIDEO_TS.IFO file to the centre of TDA' SOURCE window; follow the wizard for selecting imported track, audio stream, chapter information, etc.