Yeah the terminals were interesting. It's kind of an odd experience for a first time player to come across one of those and suddenly be flooded (no pun =P) with all this exposition on lore you're not familiar with. Unfortunately I didn't find all of them but my brother who was visiting for the week loved Halo and he was great with finding all of them so the ones I missed I now know where they are. Skulls were an entirely different matter. During my whole playthrough I only found one and he didn't find any. =P