Bitsetting in nero

In nero 6.3.02 when i select my Nec2500a under burn option it got a place where u can check mark to change bitset to dvd-rom. This same option does not show up on other dvdr tho it a 500a. So i check market it and burned a dvdr on a tdk +r media when i ran dvdinfo it shows the bitsetting as dvd+r. Does this option just not work on NEC2500a in nero? or the drive does not support bitsetting?

Thanks a lot

book type setting does not work