I too was disappointed when I received disk 5 for second season and it was just specials...don't think it should have been added as a rental. Waste of my time when I could have started on first disk in season 3!
Disc #5 in Second Season has no episodes. The special futures and deleted scenes should be added to other discs from that season; to disc #2, #3 or #4. I could have watched first disc on Season Three.