Television and Home Theater

I have a sony kp-51ws510 rear proijection tv. was working ok, but the picture was offset (pic was about 2in too low and to the right, leaving  an L shape boarder on the top and left) so i went into the service menu to adjust the Hpos and Vpos.  after finding it, saved and  worked well, on just that input i set. changed inputs after that (not in service menu at this point) and the screen got all messed up on other inputs. so tried resetting the service menu and lost picture on all inputs. What can i do to fix this now?

Daewoo 4710 Projector Tv - blue is bowed on the left and right sides. I have 2 Ic's #stk392-020.

If after installing these, the problem still is there - what might the problem?

Mat 

Hello,I have just came across an issue with my Samsung HCN473W TV while watching the screen all of a sudden it started showing a huge amount of colours horizontial lines with a weird sound coming from the back then I could smell buring parts, so i opened the back and the IRF620 chip on the sub board looks like it overheated and if i wanted to could remove it with my hands.

I unplugged the TV as soon as I could and now when plugged back in I can only hear the sound no picture. I would like to know what the IRF620 part does and what else might have gone with that chip?