If i have an operating system on one hard drive, i could just move it to my new system with another hard drive and not install it on that hard drive and that would just be extra space correct?
yep, unless the computer boots from the drive, it's just a normal drive.... i dun dat before..... took hdd out of comp with bad mobo and stuck it in another.... it still only has 90 gb of hdd space, but wut u expect from IDE?