Simple said you need a kernel, a bootmanager (i would prefer grub) and all the programs you need on the DVD. init is the first program started by the kernel. This program has to do all the things like installing, as first test it would be helpful to simply choose bash as init. (remember that this bash has to be linked statically, check this with ldd.)
For it should be very unusual that the DVD works right at the first time, try it with virtual emulation, for example with vmware.
Hope this post is helpful.