Reciently my pc pulled down its electronic pants and gave me the finger, refusing to boot up so i had my hardrive copied onto another hardrive inside my computer so i now have 2 250gb drives and then use the recovery partition on one drive to reinstall and got my pc working again without loosing anything.

Now i have 2 hardrives both with a windows folder.. i want to delete one and all the files i don't need on that drive to keep as a back up.. but how do i know which one to delete? Is it windows on the C drive or the windows on the F drive?

How do i find out?