"if you install Linux boot loader in partition, it is useless until you have something in MBR that recognize this "partition" loader and can activate it"
Thats why i was using bootpart, it is recommended in HOWTO in a debian webpage
but still i get a message telling me to insert a system disk if i choose linux in windows bootloader

Hmmm, reisntalling knoppix, and loading the GRUB into the MBR not to the Root/partition you say? is It safe? from what ive read it will mess with windows...hmm are you sure?