LCD monitors have come on in leaps and bounds over the last few years and there are now lots of good ones. If you're not going to be using it for photo editing then even a cheapo one should be good enough as they tend to have bright, vibrant colours. What they don't tend to have is a good colour range, so in very dark and very bright areas of photos you will lose some detail.
At home I have a good-quality main monitor and a cheapo secondary one and although photos look great on the second one, it really does lose contrast at the bright and dark ends. I was looking at a photo of a forest and on the cheap monitor and the shadowy places looked black; drag it over to the good screen and you could see all the bushes there.
That said, if I only had the cheap one I would have been very happy with it as it does look good.
I prefer widescreen as it's a more natural aspect ratio for your eyes - human vision is widescreen after all. However you have to bear in mind that a 19-inch widescreen monitor will be considerably shorter vertically than a 19-inch 'normal' monitor since the 19 inches are measured diagonally. To get the same vertical height as a 19-inch 'normal' monitor you'd need to go for a 22-inch widescreen.
Regards
Nelviticus