hey,
thank for all the replys,
and since I see that other people have the same problem I explane what I did.

to tschloss: try the next command for hd install: 'sudo knoppix-installer'
(I didn't try it, it's from earlier reply, and I think it's from a regular shell)

I personaly didn't try the 'tohd...' and 'fromhd...' and it looks like it going to make some problems with ntfs files.

I tried and used 'bootfrom...' and it works. BUT, it didn't work from the external hd because it wasn't mounted or someting like that at the time it was needed for booting (so I'm guessing it won't work with 'tohd...' and 'fromhd...' ).
and when I used the c: hd for 'knoppix.iso' (bootfrom=/dev/hda1) it works fine but it mounted ALL the hd as 'cdrom2.loop' and I couldnt get to this hd, not even for reading.

so, if you need access to the hd that you put the 'knoppix.iso' image on, you need other solution.

if someone knows someting else, please let as all know .

thanks, shimi