Hi Tek-69, are you using the built-in flash? What mode are you shooting in?
Since the images are turning out too dark, I'm going to assume that they are being underexposed. This can be caused by many things. For instance, if there is a bright highlight in the scene, that could cause the metering system to overestimate how bright the overall scene actually is. If your camera has different metering modes (matrix, center-weighted, spot), try using center-weighted or spot over the shaded areas. If your camera does not have this option, then frame your image and notice your exposure settings. Next, move the camera so that the little focus zone indicator is over a shady area. Do you see a difference in the exposure settings. If so, use this exposure.
Another cause is that the scene is actually darker than your camera is capable of exposing for. That is, the scene exceeds your camera's ISO, aperture and shutterspeed (and flash) combination. If you can adjust your ISO value to a more light sensitive value, go ahead and do so. Many cameras have an out-of-range indicator. If you notice that your seeing something blinking in the viewfinder, chances are that is the out-of-range indicator and it is letting you know that your image will be under-(or over-)exposed.
Is it possible the scene required a flash? Was your built-in flash active? If so, you could have been out of range (distance-wise) of the flash's output ability.
I could go on but I think you get the picture (sorry, I couldn't pass on the pun)!

Many causes can result in dark images. Give some of the above suggestions a try and see if they improve.