Do hot spots indicate the fact that heat from the earth's interior is escaping?

Answer 1

Yes. A very small portion, though.

Answer 2

Obviously volcanoes should be added to the formula.
Heat escapes earth in the form of infrared radiation.
The heat from geological sources is nowhere near the amount of heat added to the earth by solar radiation.
If the total added heat is less than the the heat radiated back into space, then there is a gain and "global warming" results.
As the earth warms, the heat radiated away from the earth increases also. A balance will result, but possibly with the thermostat set at a higher point.
If you sleep under a blanket, you have restricted the heat loss form you body so you heat up until the heat loss balances the heat gain.
CO2 in the atmosphere acts like a blanket.
There are many debatable factors in global warming, but if we are experiencing global warming, then a lighter blanket makes sense.

Answer 3

yes. Tremendous amounts of heat are absorbed and released by the earth everyday. This heat exchange takes place through the heat absorbed by the sun, the release of heat in the form of evaporation from the oceans, and other land and water mass properties. The atmosphere and properties of the earth are kind of like soup cooking in a pot.

Answer 4

Yes.