Ok now everything is good!Well the problem was (i think) a problem in the lilo installation during the knx-hdinstall setup. It simply destroyed my MBR withouth writing anything on it.
So i wanted to check if there was something bout my hd, i tried to reinstall the Mandrake 9.0 and everything worked(lilo too).
So i thought...there will be something about knoppix...
I used the testcd but it was good.
The key was: install-mbr I use it on my hd and it installed it perfectly...now everything is working good; and i Did it all by myself!
Thank you the same for interesting and trying to help me!
Marco