samsung netbook

hi,

I'm trying to reformat my netbook to get rid of my personal information (selling). I reformatted the computer successfully But my personal information are still there. My user name, password, and all my information are still there. I want to know if the netbook is a 1 owner netbook or not and if there are ways to get rid of all my personal information.


Windows 7 Starter
intel Atom Inside