Hi Barry and welcome to the forum.
What makes a photo great and not just good? Without unnatural photoshopping or anything.
A great photo will communicate something to most viewers, connect with them in some way that produces a response that makes their life richer for having viewed the image.
Un-natural photoshopping tends to degrade an image, making it look artificial or crude. All images need to be processed, whether using the preset programs built into a camera to make the choices for you as you have done, or afterwards in a 'digital darkroom', where generally a lot more can be drawn from an image with some fairly basic skills and an idea of what the photographer wants to achieve. Just like when we all shot film, the negative was the starting point, so digital images need development to create what the photographer 'sees'.
I'd leave the camera in full auto for now - the time to start taking control is when you want to make an image look a certain way and need to over-ride the camera's automatic settings to do that.
Here's a few pictures. All opinions and tips are welcome. What would have made them better?
Image 1) Your son is blurry and not sharp. Either he was moving too quickly for the shutter speed selected (most likely) or the camera missed the focus point. It's good for the subject to be sharp in the image unless intentionally using blur for effect. Try the camera in 'sport' mode for indoor shots like this.
Image 2) Much better sharpness. The lighting is a little harsh and from high overhead, which has cast shadows to make his eyes very dark - more pleasing light would either be found in shadow areas or on an overcast day, but avoid dappled lighting. The pose is pleasing, and would have looked even better if the picture had been taken from his level.
Image 3) He's obviously having fun. Comments about harsh lighting apply here too, plus he's a little blurry and it would be better to leave a little more space around him in future photos.
Image 4) The picture is out of focus. I'm not a dog person, so can't comment about whether the image would be pleasing or not.
Image 5) He's obviously having fun, again.
Looks like the camera automatically fired the flash, which has balanced with daylight quite well to fill shadows, and it's possible to see his eyes more clearly (eyes are important - they are the key part of a face that needs to be sharp for the face to appear in focus). The pic is blurry again and the area behing your son is cluttered like any normal living room. When photographing people, if you can't blur the background then it has to be considered as part of the photo, and needs to be controlled.
I hope that's useful.