650GB partition?? If you have that much data filled up you won't be fitting it on a CD. You mean 650MB?
You can create a bootable GNU/Linux CD from scratch but it will require alot of understanding and decisions.
You may want to start out by learning from using anothers' build script to accomplish this.
There exist many LiveCD bootable versions' of Gnu/Linux, you might want to download and experiment with those first.
Linux Live Linux Live is a set of bash scripts which allows you to create own LiveCD from every Linux distribution. Just install your favourite distro, remove all unnecessary files (for example man pages and all other files which are not important for you) and then download and run these scripts.
SLAX is a small bootable CD containing the Linux operating system. All scripts and source code are available and can be used to build your own Live CD.
Gnoppix is a linux live cd based upon Ubuntu Linux. It can be compared to Knoppix but GNOPPIX uses GNOME as desktop environment.
SystemRescueCD Bootable LiveCD, uses Gentoo-Linux, has options to build your own CD.
Linux from Scratch is a project that provides you with the steps necessary to build your own custom Linux system.
Tutorial
Creating a Complete Distribution on CD