KNOPPIX is a compilation of GNU/Linux software, run completely from a CD. It automatically recognizes and supports many types of graphic cards, sound cards, SCSI devices and other peripheral devices. KNOPPIX can be adapted and used as a Linux demo, a training course CD, a rescue system or as a platform for commercial software product demos. It is not necessary to install anything on fixed disk.
On The Fly: Boot Knoppix Linux, Keep Windows Installation
Article on Tom's Hardware gives a good run on Knoppix basics !