Can PERL detect how much un-used space there is on the server as well as how much room there is (used or un-used) on the server and the amount of used space? Is there a way to also calcuate the used space of a specific folder?
You are once again in the realm of modules. If you browse the CPAN archive you'll see there is a section labeled "operating system interfaces", and under that is "microsoft windows". That would certainly be a good place to start looking.