Originally Posted by Blueface

Darrell,
that is what makes it so much fun.
It is all a combination of speed with which you take the picture (more speed, less light, less speed, more light) coupled with aperture (the lower the f stop number, the more light but less depth of field, the greater the f number, the less light but more depth of field/more sharpness).
For example, with manual focusing medium format cameras that most wedding photographers used in my days, we use to set the lens to f 8, adjust shutter and flash as necessary for that f stop and hence they can set their range on the lens to a focus of 15 feet and close their eyes when shooting couples walking into a church or hall. There is no way anything within an 8 ft focus range will not be clear.

So, it all depends on what you seek. In the photos you posted, I agree with them comments that you needed to adjust your depth of field to better capture ones eye to your subject. By increasing your f stop and by reducing your shutter speed, you would have accomplished the same lighting result.
While you learn, I recommend you go with the aperture priority setting on your dial and play with higher f stops. As you do that, the camera will automatically reduce your shutter to compensate for your new setting. After you have played with that a while, you can go to full manual mode and control both as you see fit for the result you seek.