Creating a Multiboot CD

I've been trying to create a custom boot DVD that loads a menu and allows the user to select one of several things to boot into:

1) Knoppix
2) Memtest86
3) DBAN
4) GParted
5) Ubuntu
6) System HDD
7) Reboot


I'm using MagicISO to create the multiboot menu and ISO image(as it was the fastest way for me and my limited knowledge). Also, I'm using Oracles VirtualBox to test the ISOs.

Basically the way MagicISO works(or as I think it does) is that I need to create a dir on the ISO image with the actual files from the extracted ISO in question. Then I need to create a boot information file (.bif) from the source ISO and attach it to my project in MagicISO. After that it says the image is now bootable and I create the ISO file itself. This seems redundant of course since the source ISO I could burn with MagicISO directly and have work like a charm. I'm simply going about it this way to try and understand how things are working with a single image before creating the multiboot image. Basically I'm trying to do this but without any Windows distros. I've basically been trying to understand that tutorial and apply it to these linux ISOs in my project.

So far, when I try the above with Knoppix I get a checksum error or it simply hangs before doing anything at all. My guess is that I need to update it's boot file to let it know where the dir is on the DVD now. I'm just not sure how to do that and any articles on it that I find are either 1) strictly in a linux environment 2) way above my head....usually a combination of both.

Anyways, I'm doing this strictly as a fun project to learn more about how computers boot and linux and life in general, so I'm not rushing to find a solution. Any ideas to steer me in the right direction would be appreciated.