A bit more detail here : Alexnoe wrote a little command line program that can change the book type of certain brands of DVD writers. It works with the LG GSA-4163B (I have one and tested it on mine). What you can do with it is to run it from a batch file, then put the batch file in your windows startup folder. This way it will set the book type of your 4163B every time you start up your computer. Since the 4163B remembers a book type you set until your system is rebooted, it's as good as permanently setting your book type.
This isn't much use to you if you only use Nero, since it auto book types for you but if you use other software to burn DVDs (e.g. DVD decrypter), you normally have to set the book type to DVD-ROM before burning. If you are like me, you might sometimes forget to do so. With Alexnoe's utility, you won't have to set the book type anymore.