Hi I am relatively new to linux (1 year). I am 45 years of age and a computer network engineer so not a total newbie. I need someones help in respect of Nero 6 and Knoppix. At this point people usually get " Read the FAQs etc.etc. I have but I can not find an answer to my problem so can anyone help.?

I have downloaded Knoppix 3.3 from a Knoppix mirror, extracted it to a folder and brought up nero 6 to burn it. I have followed the "Choose recorder/burn image and then point it to the folder containing the files.
I have tried "all files" and get 3 folders, demos, knoppix and talks and nothing else. Under "nrg, iso, cue." it shows Demos, Knoppix, Talks, autorun.bat, autorun.inf, cdrom icon and index.html. Nero does not under any circumstances identify it as an ISO file. Is it me, what am I doing wrong. thanks in anticipation