I'm not in a position to test this out first, so if you try this and it doesn't work, then please don't accept this answer as final. I don't want you to pay for it and then not be satisfied.
In Nero SmartStart, when you go to burn a data disc, before selecting tracks to burn, there is a "more" button below (at least on the version I own). Selecting that "more" button will lead you to a place at the bottom where you can "extract tracks." Do so to your hard drive.
The part I'm not 100% sure about is if these extracted tracks from your mini discs can be burnt onto one DVD and then properly accessed. You may have to play with that a bit.
If you are able to leverage this answer and do exactly what you hoped, then my wish is that you come back here and accept this answer. If not, then please let the experts know what worked, what didn't, and where you are stuck, and we'll confer amongst ourselves to see if we can help you get the rest of the way through this project.
Thanks for using JustAnswer, and best of luck to you.
Gary
