* Select a digital camera with a maximum resolution that meets your largest output you're likely to want. If you want to make 8-by-10 prints, we recommend a 4-megapixel model, though a 3MP camera will do the job. A good 8-megapixel camera can take you all the way up to 16-by-20 prints. If all you want is to take pictures for e-mail or the Web, even 2MP camera will suffice. And remember, megapixels correspond only to image size, not quality.
* Make sure the camera has the right features for your needs, such as video recording, an optical zoom lens—perhaps even manual controls and a histogram. If you wear eyeglasses but like to take pictures without them, make sure that your camera has a focusable diopter, which lets you adjust the focus of the viewfinder so you can see your subject clearly.
* Choose a model with a bright LCD so you can see it when shooting outdoors. And make sure the screen is large enough so you can easily compose and review your images on the camera.
* When comparing costs, don't forget to calculate the extras that may or may not be included, such as rechargeable batteries and a charger, , and a memory card with a high enough capacity to hold all your pictures until you can download them to a PC.
* Nearly all digital cameras have a USB interface. For higher-megapixel models, try to find one that supports USB 2.0 so you can transfer large image files quickly.
* When looking at digital cameras with a zoom lens, what counts is the optical zoom—not the digital zoom. Digital zoom is actually a software function that involves cropping and magnifying an image, resulting in a loss of image quality.
* If you don't know an f-stop from a white balance, a digital camera that has lots of modes and manual settings will generally be overkill for your needs, as well as being higher in price and more difficult to use.
* Look for a digital camera that comes with a pocket-size instruction manual instead of one on a CD-ROM. It's easier to consult when you're out shooting.
* For small, young, or arthritic hands, look for a digital camera with a limited number of buttons, and make sure they're large and easy to access and press.
* Test how fast the camera performs. You will probably be unhappy with any digital camera that takes longer than 4 seconds to boot up or longer than 6 seconds between shots.
http://www.camera-4u.com/digital-cameras/digital-camera-top-ten-buying-tips.htm
