Perhaps you should pick up 'understanding exposure' for a fab book on the basics.
1) There's no such thing as 'you should shoot'
2) low DOF is what htid is suggesting you do. And to do that you need a larger aperture.
3) Larger apertures have small f numbers. F is a reciprocal - divided by the number. So likewise the larger the f number, the smaller the aperture, and the bigger the DOF. So you're doing the opposite to what you want to be doing.
4) Sunny 16 is a just quick way of estimating how to get the right exposure. You have zero need to worry about that on a camera that has a light meter built in.