I need to install a Windows OS on Bootcamp for one small application. Any recommendations as to which version to buy and where to buy it cheap? I'm running a Mac Pro 2.8 Xenon. I'm confused with stuff like Home Edition, Pro Edition, Ultimate, etc., Service Pack this and that... It seems like the latest Windows is 7 and it needs Snow Leopard. I read Windows 7 can be installed on 10.5.8, but will require some hoop jumping. I just an Windows OS, just about any at the lowest cost. Thanks.