Combine rice, cinnamon and lemon zest in a medium saucepan. Toast over medium-low heat, shaking occasionally, until rice develops a nutty odor, about 5 minutes.
Add water and cook over medium heat, stirring occasionally, until most of the water is absorbed, about 4 minutes. Add 1 c milk and continue cooking, again until most of the liquid is absorbed, about 6 minutes. Add the remaining milk and cook until most of the liquid is absorbed, about 7 minutes. Add sugar and salt, stir well, and and cook until sugar is dissolved, and the liquid is nearly totally absorbed, about 3 minutes more.
Remove from heat and stir in creme fraiche. Serve hot, or chill in an ice bath, then refrigerate, covered, up to 2 days. (Place a sheet of plastic wrap touching the surface of the pudding to prevent a skin from forming before sealing the container. Leave cinnamon and lemon zest in; they will continue to add flavor. Discard just before serving.) Serve cold, or reheat gently in a saucepan, adding more milk if too thick.