How to uninstall fedora on dual boot system

[john]

Hello everybody,
                         My problem must be deadly simple for most 
people but for me it leaves me shivering. I have now two computors and I 
want to reinstall fedora on the second which is so muxh better than the 
first. On the latter I would like to get rid of fedora and leave windows 
which unfortunately I have to keep : the kids and the wife! How do I do 
this without having terrible trouble with Grub? Could you please 
indicate the road  on how to avoid a breakdown on the computor and 
logically, if things go bad, n nervous one for me. Thanks in 
advance      John Brennan-Sardou.