What Paint to use for Painting Interior Concrete Blocks

[tomq42]

I have a garage with interior walls made from *paint grade* concrete blocks.
So clearly I can paint them :-)
Question is what do I use?
Do I use exterior smooth masonry paint, or do I use standard interior emulsion? Interior emulsion is presumably designed for smoother surfaces, but I don't need the weather/sun protection of the exterior masonry paint.

Also, do I need to seal at all? Do I even need a mist coat, since the blocks won't such up moisture as much as fresh plaster would? What about the mortar?

Any other tips welcome.

Thanks.