I was forgetting to set the options on mkisofs beforehand.
Now i burned a new one, and it does work.

However, the emulated game is bigger than my screen, and i havenīt seen a way to make it smaller.. is this suppose to go like this ?
seems weird.

Anyway.. NesterDC is quite cool, the games plays at full-speed, full sound.. seems nice.
I will toy with it more tonight after work.. but the first impressions are good. Now if only i can solve this image size problem.