Sure that's a good idea, but the OP wants to somehow format back to having an OS. DBAN wipes the harddrive clean leaving it without an OS. The only way to get what the OP wants is to run a reinstall disk, if the computer came with one. If there were a way to format a harddrive and end up with an OS, everyone would be doing that and not paying for Windows.
But if you have a way to install Windows again, DBAN is a great way to make sure that no one will ever pull anything you had off of your harddrive.