After a few flights, you’ll learn to recognize the weapons from the cockpit.
Yes, salvo and ripple both work. The only multiple-release pylon holds 2 or 4 100’s, and they are released all at once.
The selection of dropping 1, 2, 4, or “all” refers to the contents on the pylons. So, in theory if you select “2”, the weapons control will drop two bombs (unless one of the pylons hold 2 100’s, then 3 bombs will actually drop. The lonely bomb on one pylon and both of the 100’s (which are released together), separated by the time interval selected.