Skip Knoppix & the LiveCDs and go directly to Debian. Debian developers have shipped Debian 3.1 (sarge) Mon June 6.
Debian stable - http://cdimage.debian.org/debian-cd/...86-netinst.iso 108M
The minimal install is about 200-300MB and includes only the basic shell, etc, filesystem programs, apt and dpkg programs so that you can get updates and install more packages.

I hope this helps.
James