Windows 7 Does Windows 7 Include Drive Wiping Features Worth Choosing Over Wipe Drive Pro?

Hi, I am thinking about purchasing Wipe Drive Pro for $90.00. Alternatively I could purchase the new Windows 7 if it had a feature to wipe my drive clean of older files with some kind of encription tech. I would rather spend the money on Windows 7 if it had this. Does anyone know if any of the latest versions has such a built in program? My Mac has this so I thought that Windows may have stepped up to the plate as well with this latest release. Any thoughts? Thank you.