They there, this is Mirthy's hubby, the camera expert of the two of us so not saying a heck of a lot there but here goes.
The problem is that the focus is not the foreground like you wish but the background. Usually this is caused by what you are focused on. Most cameras when you press lightly on the button it focuses on the center of the image in view although sometimes your settings might change this, such as focusing off center or looking for a face to focus on. Another problem might just be that the very center of the photo wasn't on the dragon. There is also the possibility that other factors affected the auto focus, like the sensor is dirty, or there is something that the sensor is picking up rather than what you wish to focus on, like the glass of a viv. But simple experiments might help you find where the focus likes to be. Put a very obvious object like a wine bottle in front of you close on a table and focus on the very top of it it while keeping the table out of the shot. The auto focus will auto adjust when it is in the spot that it likes to favor. move above the very top of it until it focuses on something other than the bottle and then to the right or left until you find the sweet spot. Or you just have to work with manual focus to get it right if it just doesn't want to work for you.
Ok the next thing to cover is aperture. Its represented by F4 to F20 or so, the lower the F number the more it focuses just on the subject and it blurs the rest while the higher the number the more it draws everything else into focus, making for less blur....the advantages? well other than what was said, the more you want in focus the more light needed. F4, for instance requires less light. F20 works well outside during the day....Now for the look, for a portrait, using the lower numbers makes for a better look, making the focus of the picture be more important and the rest softer, the higher numbers lessen this effect until it basically draws everything into focus, so using the F20 might solve the focus problem.
If you want more I can do shots along with explaining everything. I tried to simplify things a bit but can go into greater details and technical jargon, If its a digital, just keep shooting until you get these points down, and as always, have fun with it.
((and hi from Mirthy, too!))