Bring rice and water to a boil in a saucepan over high heat. Reduce heat to medium-low, cover, and simmer until the rice is tender, and the liquid has been absorbed, 20 to 25 minutes. Stir in rice vinegar and salt. Allow to cool completely.
Lay out seaweed sheets. Moisten hands with water, then spread cooled rice evenly on each sheet, leaving a 1/2-inch gap along one edge, lengthwise. Arrange strips of cucumber, imitation crabmeat, and cream cheese on top of the rice in a straight line along the side opposite the gap. Roll up sushi from the toppings to the seaweed sheet's exposed end.
Using a sharp wet knife, slice each roll into 5 or 6 pieces. Serve with minced ginger on the side.