You can discuss it right here.
Don't waste your money on McAfee, I would recommend you use Microsoft Security Essentials
instead. It is free and is much less bothersome than McAfee.
If the computer is truely in sleep mode the hard drive shouldn't be doing anything. Either the computer isn't really asleep or it is something else. Are you sure it isn't normally scheduled tasks causing the hard disk activity? E.g. a scheduled virus scan or defragmenter running. Those things tend to be auto scheduled for the early morning hours.