What make and model is your burner or reader? Always give as much information as you can when posting. It's possible that there is firmware that will enable it to use dvd+ media. On the other hand there may not be.
I don't think theres a magic program outside of a possible firmware upgrade that will suddenly change your burners capability. There's also potentialy the hardware incompatability of the laser I think.
This is not my personal area of expertise, if I have one, so hopefuly someone else will be able to help out. I've not had a burner that can only handle one format. In fact, I thought +r could be read at least, if not burned in any PC dvd drive. Live and learn...