You do have to install Windows first... It likes to be the primary partition. If Mandrake's anything like SuSE (I think it is), it's pretty good about either letting you resize your Windows partition after Windows is installed. I know that SuSE even gives warnings re: "You're deleting your windows partition." It's also pretty good about plunking itself where it's meant to be. I would imagine, since Mandrake is also good for beginners, it's much the same way, or pretty similar.