Television and Home Theater

Got a Toshiba 61H70 and it just resently started to turn off by it's self you have to un plug it to turn it back on but only staysfor about  8 min then turns back off and it started having some horizontal lines accross the screen hopfuly some one can tell me what is wrong with tv please?

Phillips 9p6034c102 60" rear projection,  Has any one else experienced this problem?  When first turned the picture will shrink to aproximatly 36" and expand to full size back and forth for 10 or 15 minutes untill set has warmed up.  It has also shifted about 1" horizontal to the right.  The Repair shop estimated 400.00 to 700.00 for the repair.  Could this be a faulty resistor or capcitor @ the circuit board that could be removed and re-soldered.  I am not afraid to tackle any job and I am handy with a soldering iron.  Thanks for any h

Ok, heres the problem. I have a 27" Toshiba with a digital projection tube. When I switch to an input channel and play any of my game systems I get two clouds of color on the screen. Green on the left and red on the right, they fade away and come back periodicaly. I can make it go away by turning the tv off, but after a bit it does it again.