This should be easy, but I am stuck.

Got Knoppix 5.1.1 from "Linux Magazine" (April 2007).
I cannot boot from DVD, so made floppy image from "Baldur.img"
(Help on DVD says use "Boot.Img" as image file (but Baldur.img is only .IMG file on DVD)

Anyway.

I made and booted from floppy into dos, ran loadcd.bat so I can now see the CD
however I don't know how to start knoppix from this dos prompt.

How hard can it be?, but I can't do it and can't find this in the FAQ