Television and Home Theater

I'm not sure if this TV is the WS55511 or WS-55711. The manual is not too clear on this.

This tv is about 4-5 years old. This problem has been getting progressively worse over the past few months. The TV will turn on just fine, and after awhile (from hours down to minutes) we've been getting dancing horizontal black lines, and then the TV winks out. Sometimes it'll wink out with the lines as well. Occasionally, the very top and bottom of the picture (1-2 inches) would shrink horizontally as well, usually in conjunction with the black lines.

i was given a samsung HC-P4752W the tv seems to shut itself off after it warms up this problem has just recently started but before it was shutting itself down the picture was really distorted. im really just tryin to figure out how to make it stay on with a clear picture please any input would help!!

When we try and turn the t.v. on it makes noises like it is going to turn on but does not.  We have to push the power button several, several times before the t.v. will actually turn on.  Sometimes the power light will come on and the screen won't and it will make a very loud noise.  When we turn it off and back on after it does this it will usually come on.