Place water and salt in a saucepan that has a cover. Bring to a boil. Add rice and cover. Cook over low heat for about 25 minutes until done. Meanwhile, carefully grate the cheeses and chop the green pepper and olives if you choose to use them. If you like corn you can use some frozen corn according to the instructions on the package. When the rice is done put it in a serving bowl, mix in the vegetables, the monterey jack cheese and the yogurt. Then stir in the cheddar cheese and cover the bowl for a few minutes so the cheese can melt.