Changing booktype DVR-215D

I am using IMGBurn but I can’t change the booktype of my dvd. I know I have to crossflash(?) with buffalo(?) but I have no idea what it is or what it does.

It says I’m using a “Pioneer DVD-RW DVR-215D 1.19 (ATA)”. What I want to do is to burn using a dvd+r but change it to dvd-rom.

If someone could tell me where to get the stuff I need and explain a little bit what it does and how to use it, I would be very thankful.

Take a look here for a pointer in the right direction.