you can download Dariks Boot and Nuke Program(DBAN). You will need to burn the downloaded ISO image to a CD or DVD. it has several disk format options.
Why can't you format the drive? Do you get some kind of error message?
Here's how you can format a drive: http://products.wdc.com/support/kb.ashx?id=pfdOpr
Keep in mind that this is data destructive and you need to back up your data first.
you can download Dariks Boot and Nuke Program(DBAN). You will need to burn the downloaded ISO image to a CD or DVD. it has several disk format options.