Depends on what OS it was and what one it will be.

linux acctually, xubuntu to be exact

from linux to linux?

Basically just format the partition from the boot disk. That will do it.

that like just re-installing?

Part of the reinstall is HD config where you can re-format and change partition settings. Which you would know if you actually watched me.

oh i watched you...what i didnt was understand what i was looking at its alright though, I found out how to write over all the code

and re-install