need help regarding game objects beginner

hi friend i have two game objects first is player that contains a camera and the second gameobject is another camera named as "quality" . so what i want to do is on pressing ESC key i want my player game object to get disable or inactive and the quality gameobject to be enabled . and on second time i press Esc key then it should be opposite means the quality get disabled and player gets enabled. plz help me i have gone throught all the tutorials but cant get success .. if anyone can provide me some help