The display screen in the back is lighting up but it is too dark to see. How can I increase the brightness of the display...

Make sure you turn the camera on and the lens extends. Then on top of the camera, to the left of the power button, you'll see a button labeled 'F.LCD'. Press that and it should respond for you.

First, make sure that the lens is clean. Then make sure that your camera is in SMART Auto mode, that will auto focus your camera. Then, when you are ready to take your picture, half-press the shutter button, to force the camera to focus, then fully press it to take the picture. This camera will do all of the work for you to ensure you get the best picture.