Insulate Cellar?

This is a pic of the ceiling of my cellar. There is no access from inside the house and I was wondering if the lack of insulation is the cause of the first floor being cold all the time.

This is how I bought the house and the inspector said i did not need to insulate. The cinder blocks you see the beams of the house sitting on is exposed to the elements so would it be safe to say I am loosing heat through the cellar?

If so how do I insulate the cinder block wall?