Draining the water from the "pump" (I'm assuming you mean the filter) should only take a few minutes.
How long it would take to drain the water in the pool down to the winterization level would depend on the size of your pool and the pump you are using.
no you don't that isiligal
If your pool is above ground it does not matter, But if your pool is in ground and you drain it it will act like a boat and float if the water table rises.
Drain the oil, not normally. Drain the coolant, yes.
Yes
Not all above ground pools have to be disassembled during winter, although it is a good idea to drain them. Water expands when it freezes, and if the water is trapped in a closed container or in a crack, the expansion can break the container or the material surrounding it. Pipes often break, when water inside them freezes.
drain
drain
You're supposed to drain your pool for the winter so that a layer of ice doesn't form, expand, and crack the sides of the pool.
ground
ground
No
Normally on the bottom of the radiator. You can always just remove the lower radiator hose to drain it.