Preheat oven to 375F (190C). Pierce the potatoes with a fork and bake for 1 hour or until tender. Allow to cool, and cut a thin slice off of the top of the each potato. Scoop out the pulp, and place in a small medium bowl. Add the salt, milk and butter. Beat until it is fluffy. Beat in the sour cream and cream cheese. Spoon the mixture back into the potato shells. Place potatoes on a baking sheet. Sprinkle with paprika and bake, uncovered at 350F (175C), for another 20 to 25 minutes, or until heated through and tops are browned.