HD Install :: mount does work but saving not

i mounted sucessfuly something called something like "hda_0"
but when i try to save a file on it a error occours something like" hda_0 is not a write system"
whats wrong?
i have some empty unpartitoned space on my hd can i try to format it with dsl?

i have installed dsl on hda5 now i think it will work

uff iam so happy that i catched the right hda otherwise i couldnt go
online anymore

original here.