Each type of TV has their own unique benefits. You really can go wrong. Plasma TV's are probably the cream of the crop. The are designed to give you the best picture quality than LCD or DLP TV's. You get a larger screen size with Plasma flat screens than you do with the LCD flat screens. Plasma TV's have a glass front to protect the screen area, sometimes susceptible to breaks or cracks.
LCD flatscreens are great also. They will use less energy than plasma tv's. The lcd uses crystals to create it's picture giving you a clear, brighter picture than plasma flatscreens. LCD flatscreens are more flexible as well because you can use them as computer monitors as well. LCD's are better for video game play because you won't get burn in.
DLP tv's are the best in my opinion if you have the space. You get the larger screen size than you do with plasma tv's or lcd's. DLP's work off of the same premise as the old projection screen tv's but with better picture quality. DLP's have a series of mirrors that create the image on the screen. DLP's also will offer a brighter picture for the viewer because it has a bulb inside the unit. Maintenance on dlp televisions is easy and simple, when your picture goes dim, you replace the bulb inside the set and you have a new tv.
You can't go wrong with either tv. If you have the space I would recommend the dlp television for the picture quality and screen size. If space is a premium and you are looking for something to give you rich colors for HD movies and programming go with the plasma. If you are a gamer and tv watcher I would go with the lcd, no burn in, brighter picture great dependability.
I personally own a sony dlp projection screen, 50 inch.