Blue LED not switching off
Every time through your loop, the LED is being set to HIGH voltage. This may or may not be followed by setting it to LOW voltage, but since the loop runs again immediately, it's immediately set back to high voltage. This happens so fast that the LED essentially "feels" half voltage and it will dim. Your code needs to be more like this...

void loop() {
  if(digitalRead(10) == LOW) {  
    digitalWrite(13, LOW);
  } else {
    digitalWrite(13, HIGH);
  }
}


OR... even like this...

void loop() {
  digitalWrite(13, digitalRead(10));
}