Firstly, download the above code. It is a boot sector program written in Assembler. Then, follow the instructions on compiling inside the file.
Once you have compiled the file - you should have a BOOTSEC.BIN file.
Now, you can issue the following command
mkisofs -b BOOTSEC.BIN \
-o bootcd.iso \
-no-emul-boot -boot-load-size 4 -boot-info-table \
-J -r -T \
-p "root@skiddies.cx" \
-A "Boot Disk" \
cd_top_area
cd_top_area should be a blank folder at the base of the system. Such as C:\boot
Then, take the bootcd.iso file and burn it to CD. Insert it in the CD-Drive at system boot and watch the magic!
This is just the beginning - you can modify the BOOTSEC.ASM file to suit your own requirements.
For example, you could print out 'Xander is a 1337 hAx0R!
This boot sector program will only print out the registry values of your machine at boot. It will not load a kernel or do anything else!
Most importantly - READ THE BOOTSEC.ASM FILE!