I have always felt that the greatest use for a UV filter was to protect the lens.

Beautiful work. Just my kind of beach.

You are not the only newbie here.
No you don't need to take the uv filters off when adding another filter to the lens.

A lot of this is going to sound very basic, but anyway.
Pre- set your exposure and focus if possible.
The best motion stopper is a flash-1/2000 of a second speed- if you can't do that use the highest shutter speed and widest aperture you can get away with.
Use a tripod if possible.
Panning with the motion results in a blurred background, often very desirable in motion shots.
The bigger the aperture the more critical the focus will be, the smaller the depth of field.
I hope that this helps.
Brodie

The smaller the aperture the greater the depth of field-the more will be in focus beyond your subject-. Select an aperture that will allow your subject to be in focus , but not the background.