I would forget about the contents of the drive as they are not likely to fix your drive and hand it back to you, what normally happens is if the drive has to go as far as the manufacturer its normally so they can see what went wrong and swap it out for a repaired one on a production line method, this means they can have a fast turn around, if they fixed your exact drive to return to you it would take them a lot longer to do all this and keep track of folks personal data, simply erasing all the drives contents shields both them and you from any liability for the drives contents, btw simply having the winmx program on your drive does not mean you used it to download any files, nor that you dont actually have all those files on the drive as a backup repository for your collection of media as many folks do, and on a final note unless your selling those files or otherwise allowing unauthorised access to them for profit you haven't actually broken any laws in downloading them, as I often point out its uploading them to others that incurs the legal wrath not downloading for your own usage and research.