formatting hdd after mandrake install

I recently installed the latest edition of mandrake on a spare 20gig hdd that I had lying about. I hadn't tried mandake before so I thought I would give it a shot, didnt really see anything special about it. Im a total linux noob, so I was wondering if anyone knew how to format the hard drive so I could put windows on it. I have another 40gig drive which I managed to install red hat 8.0 onto and I prefer it to mandrake, so want to keep that, but I also like my games, so use windows for playing online games.
(sorry for saying the evil windows word)
Could anyone help me out formatting the drive with mandrake on it please?
Thanks for your help people! :D

Well i don't see problem ? Just insert win98 disc in drive .. setup your bios to boot from CD-ROM .. then Boot with CD-ROM .. then go to drive with your win98 disc .. and type format <drive> .. and that's it ? =) if you have partitions other that linux .. yous should use fdisk ..

cheers...