Chapter 1 is an introduction to the cast of boys that are stranded on the island. The reader first meets Ralph and Piggy. It's clear right away that Piggy is quite intelligent. He suggests to Ralph that he blow on the conch shell as a signalling device. That brings Jack, the choir boys, Simon, and the Litluns. An election is held to nominate a leader, and Ralph barely edges out Jack. Jack is made into the lead hunter. Ralph, Jack, and Simon leave to explore the island.
My picture recommendation for chapter 1 is a picture of a conch shell. It plays an important role in chapter 1, and it continues to be a symbolic image of leadership and rule throughout the rest of the story. Image linked below.
Chapter 2 begins with Ralph blowing the conch shell. Ralph and Jack inform everybody of their dire situation. It is decided that at group meetings, whoever holds the conch shell gets to talk. One of the boys mentions that he saw a "beastie" on the island. Everybody freaks out. The older boys calm everyone back down. Ralph suggests that the boys need to make a big signal fire. Being teenage boys, the thought of lighting stuff on fire sparks everybody's interest (pun intended). Piggy uses his glasses to light the fire, which again shows his intelligent value (but nobody recognizes it). The fire gets out of control, and a boy goes missing.
My picture recommendation is either a pair of glasses or a picture of fire. Piggy's glasses would be my first choice. They are symbolic of Piggy and his potential, and they later become a tool of power in the book.