1)They have no defense as far as i can tell so do i even roll or is it just if you are in range you hit?
They have a fixed defense ratio of 1-1 rather than a Defense number. You _always_ resolve attacks on treads by rolling a die and comparing to the 1-1 column.
the infantry did one tread damage per attacking squad and everyone else did one tread damage per attack, even heavy tanks. That seemed wrong.
That is wrong. The number of treads removed is equal to the attack strength of the attacking unit; your instincts are correct. That must have been a very rough game on the defense :-)
3)I know it very clearly says D results have no effect on Ogres. I assume that includes their guns? So i cannot disable a battery or missiles for one turn yes? I had a thought it might be just for tracks...
That applies to _every_ component on the Ogre; batteries, treads, whatever. Since you mentioned missiles, it's also worth noting that Ogre missiles are single-shot weapons. Firing one is the same thing as it being destroyed by an attack; check it off on your stat sheet.