wait wait wait, I know what your talking about now, but that comes much sooner in setup, at the same time you hit f8 to install a fresh copy I thought you were talking about not formatting and just deleting the windows folders, because that's 99% of the time a bad move. After hitting F8, select your drive and tell it to quick format as an NTFS partition.
No no. I'm not stupid enough to recommend that to someone.