Maybe a frozen brake caliper yes most definatley a frozen brake caliper or possibly a pebble or small rock lodged between the pad and the rotor. I had this same problem with my 93 YJ new brakes and it was good.
Because your jeep wrangler is over heating, you must have a sensor in the dash not working If that smoke is steam, the heater core is leaking and in need of replacement.
Probably a blown or leaking head gasket.
They are loose or worn out. Also can be a pulley with a bad bearing.
White smoke is steam. A little is normal on all engines. If there is a lot it could be an indication of coolant getting into the exhaust, possibly from a failed headgasket.
The black smoke could indicate worn piston rings. This would allow excessive amounts of oil into the combustion chamber and cause misfires and generally low engine performance.
It means it's running rich (getting to much raw fuel) You need to get it checked out because it can be a number of things from a bad o2 censor which is fairly cheap to a blown head gasket.
No
it is harder to drink and drive
smoke
It's the fuel from the engines.
You can drive a diesel engine, or any other type, blowing any colour smoke you wish. Though it is pretty foolish to smoke
Not any more than any other vehicle, but the weak point is where the exhaust meets the manifold. a new clamp and gasket will improve things a lot. Sometimes a crack will form in the manifold itself, this can be welded in most cases, but is hard to detect without a smoke test.