Bring 1 1/2 cups water, rice, and salt to simmer in a heavy large saucepan over medium-high heat. Reduce heat to low; cover. Simmer until water is absorbed, about 10 minutes. Add milk, cream, and sugar. Scrape in seeds from vanilla bean; add bean, or stir in vanilla extract and cinnamon. Increase heat to medium; cook uncovered until rice is tender and mixture thickens slightly to a soft, creamy texture, stirring occasionally, about 35 minutes. If mixture seems runny, not to worry, it will thicken up as it cools.