MY TV TURNS ON AND STAYS ON FOR 5SECONDS AND THEN THE SCREEN TURNS BLACK BUT CAN STILL HEAR THE SHOW PLAYING. TURNED IT OFF AND EVEN UNPLUGGED IT FOR ABOUT 5 MINUTES, BUT STILL THE SAME THING HAPPENS.

The lamp is likely bad .. they only work a few thousand hours .. then must be replaced .. your lamp can cost a couple of hundred (maybe even more if bought locally) .. here is one for less if you have someone handy that can change it.......
http://www.purelandsupply.com/50PL9126D-37-Bulb-Philips-DLP-TV-Bulbs.html
..... of course make sure power is off (unplugged) and make sure things are not hot .. there is usually a little cubby in the back where the lamp is located .. you an see what the lamp looks like at the above URL .. dont get finger prints on the bulb . that will cause it to crack when hot .. if you are unable to change the bulb then a call to philips service should do the trick. make sure you ask what the bulb replacement and labor will cost ..