1st circuit
The voltmeter gets its reading V from the lower cell, initially. It's across the terminals of that cell.
When you close switch S1 you just connect in parallel another cell of the same voltage. So the meter still reads V.
Same voltage across the bulb (V) means the same current as before.
So you are correct that there is no change and the 1st two are false.
By the way, it is important that the internal resistance of the cells is negligible (ideally zero) for this to be true.
Circuit 2.
Correct.
The readings on both ammeters will decrease.