Free Software Magazine have reviewed Knoppix and the title kind of gives it away.
Read it here
Knoppix is probably the quickest and easiest way to try out Linux, and I hope you will. Linux is a vast world of almost infinite possibilities that Knoppix makes easy to explore.
For more experienced Linux users, Knoppix makes a great way to try out different configurations. If something goes wrong, a simple reboot will bring it all back to normal.