Welcome to the forum Ian,
I really hate to be the bearer of bad news, but I think you will have to learn a few things before getting the results you would like from your camera's settings. There is no magic setting for any situation, and photography basics play a major role in quality pictures.
I would recommend that you read and study your camera's user manual and find a few basic photography books to learn how image capture works. There is a question of light that could be compared to a liquid. You need to understand that the shutter speed controls how long the light gets in the box and the aperture controls how fast the light gets in. Think about filling a bucket of water, it all depends on the size of the bucket, the pressure and how you open the faucet. The iso would be the size of the bucket, larger iso meaning smaller bucket (need less time to be filled). Aperture allows the light to get in faster (smaller f number) or slower (bigger f number). Then there is the unchangeable, how much light is there? Sometimes there is just not enough to get the shutter speed and aperture you would like to get the results wanted.
Some people think that by just getting a better camera they can take pics in the almost complete darkness (babies in cribs for example). It just does not work that way. There is no magic in photography. It just need light, sometimes lots of it. And this, only experience will teach.
So, my suggestion is, keep at it, read all you can and practice. Only practice will teach you how things work. If you only try one setting without understanding why it works, you will not be able to get better. Situations change and you will need to work with a lot of different settings.
Enjoy your Nikon!