In general, a standard fireplace is not the most efficient method of heating your home. A substantial amount of the heat produced is lost up the chimney. Depending on your local regulations, an efficient wood stove or fireplace insert would be a better choice.
Always consult with a local qualified expert before installing any heating system.
Not a good idea. People that designed your gas fireplace did not design it to have a separate heat source in there with the gas piping and controls.
Potatoes would be heated by a fire and use the hot potatoes as warmth.
The sun, pool heater, microwave, fireplace
I'm an old (75) country boy who lived by a fireplace all my life, until I was in my 20's as the only source of heat besides the wood stove in eth kitchen, and I've never heard the corner by the fireplace to have a special name except "the corner by the fireplace." As in, "Stand it in the corner by the fireplace."
To the left or right of the fireplace but not above it, you can use trunking to make the wires look nice and neat. The heat from the fire is not good for your equip and heat rises.
Furniture and fireplace stores will have fireplace rugs. However you can get some regular rugs for this. Most people prefer the fireplace rugs because they are heat resistant and can withstand hot conditions.
Better, in a heat efficient way, because there is no loss of heat, with a real one,you need to vent exhaust fumes and at the same time you lose heat. A real fireplace looks better but is less efficient.
The fireplace's heat is an example of radiation.
They would be felt as heat, such as the warmth radiated by a fireplace, or by the sun on a clear day.
YES, you could use those little tanks for a fireplace (providing you have the proper adapter and gas regulator. BUT it won't work for more than a couple hours. The BTU output is to great for such a small canister and the pressure drop causing carbon monoxide (from the fireplace).
Fireplace
When it burns, it produces only water and heat. Good stuff.