Hehe, you most certainly don't want to run format. It won't let you run it on your main drive, but if you have a 2nd harddrive, it will wipe it clean. NO data will be left on it what so ever.
I'm not sure what Wipe free space is(possibly something with XP, but I'm running my 2k cmop right now) but some the little I found on the net, it works just like format. So no, i don't think you'd want to run it...