I have a 1TB hard drive with all my games on it and I would like to merge it with another 1TB drive in my pc and use them as one big drive. Doing this will delete all the data on both disks which would take years to re-download I do have a spare harddrive of 250GB or so can I make a compressed back-up of one of my drives and put it onto my 250GB drive so I can merge the other two?