To save the boy, you need to sacrifice yourself. It will not kill you, but will permanently remove some stat points (random, often 3 points). There are several items that can boost your stats or level, which more than make up for this, however.
You need Lockpick for the door, or Telekinesis for the lever (both level 2).
You can leave this quest until you are stronger, or are able to buy a couple Telekinesis spell books.