If the mpu board has a socketed chip that says "SSxxxx" on top I think that means the machine is an S+, not an S. Also, on an S machine the mpu board is connected to 2 large wiring harnesses that have connectors attached to the edge of the mpu board. On an S+ the mpu board plugs into the motherboard below it.
Where the power cord attaches inside the machine there is often a "line filter". This is an electrical part meant to block electrical noise/spikes. If it is bad you can bypass it, not necessary to replace it for home use. The parts that are burned may be wafer capacitors or varistors (spike suppressors). If these parts are defective that can mean electricity is not getting past them and into the machine, so it will be dead.
But photos will help answer all of these questions.