Panasonic had the same issue with their DMRES-15 DVD recorder ....what happens is the laser motor breaks down and does not return to resting position.
your case sounds a bit different but doesn't sound like you can fix it.
take the power plug out of the wall socket.
unscrew the screws on the external case and lift open, to get the disc out. try powering it back on after the disc has been taken out.
if it still won't power up - it's off to the repair shop ...though a brand new one would be cheaper.
Jason
January 2008