Since customer service is important to you, avoid K and Wal

Mart. I'd go with Circuit City/CompUSA first among your choices for choice and service. Next Ritz for service, though probably less choice, and last on the remainders,. Best Buy.
CC, Comp and BB all have priceguarantees, so you're equal there.
Handle the cameras to see which is most comfortable. If you expect to use it outside, make sure you have a viewfinder as well as the LCD screen, which will be very hard to see in bright sun. Make sure you have white balance and a macro funciton.
Bigger megapix are good for printing enlargements but make posting on line a pain, especially if you or your audience have dial up connection.
Try to avoid a docking station. A direct USB is simpler. Look for something with a good rechargeable battery. If you can get one that will interface with the camera to tell you how much time you have left on it, all's the better. (Sony's "infolithium" battery will do this.)
As with any camera, and especially if you're doing close ups, an SLR style is best, where the image in the viewfinder is exactly waht is coming through the lens.