Let's begin by reviewing the basics about these two works of ancient art. The Stele of Hammurabi is an over seven-foot-tall black stone pillar inscribed in cuneiform with the law code of Hammurabi, the king of Babylon. Hammurabi ruled from 1792 to 1750 BC and established a set of 282 rules designed to govern trade, enforce justice, and regulate punishment. To grant legitimacy and solidity to these laws and to make sure that they would stand the test of time, Hammurabi had them inscribed on stone with an image of himself receiving the code from the Babylonian god Shamash, the god of justice. The carved image is simple yet elegant, with the figures shown in relief.
The relief of Darius and Xerxes receiving tribute is found on a stairway leading up to the Apadana, the audience hall of Persian King Darius I and his son and successor Xerxes I, who ruled over the Achaemenid Empire from 522 to 486 BC and 486 to 465 BC, respectively. The relief, which is made of limestone and stands eight feet, four inches high, features Darius on the throne with Xerxes standing behind him. The two are receiving tribute from small figures in front of them while being supported by smaller scale followers standing behind them. The piece was originally painted with brilliant colors of purple, blue, red, green, and turquoise, but it has since lost its pigment. The figures are all shown in relief but also in stylized detail.
With regard to the second part of this question, certainly modern works of art still tell stories and deliver messages although perhaps less so than in previous periods because of the rise of abstraction. Think, for example, of the American artist Normal Rockwell and his delightful paintings that illustrate American life, ideals, and social issues. His art captures everything from the first moon landing to a family Thanksgiving meal to Rosie the Riveter of the World War II era. Each of his pictures tells a story and delivers a message.