Well......you have found the blade engage lever and switch.Should have one on the clutch pedal/brake pedal also.May have one under the seat,but usually they kill the mower with the blades engaged.I usually just jump across those switches with a short piece of wire.Pull the wires off the switch and put one end of the wire in one side of wiring harness and the end of the wire in the other side.You can pull wiring harness off the key switch and clean that up really good.And you can check all electrical connections.I am assuming the battery is good and charged and the cables are clean and tight????Keep us informed!!!jc