This is not the way a compressionist goes about getting content to fit onto a DVD.
The idea is to compress media (video, audio, animation, gfx, etc.) with compression software. The amount of compression depends on 2 factors: File Size and Quality. The point is YOU control the compression, not software.
That said, when we're in a pinch, we do what we can to find what works and we make it work. Next time you may run across across the practice of bit budgeting. Have a look at this: Bit Budget