I'd say row 1 is less private because you are much nearer the people on the other side of the aisle. I'd say that in the front cabin row 4 gives the most privacy if that is what is wanted (furthest space from other side of the aisle, no one behind you so you only have people on two sides and not 3).

However, the overall most private pair of seats would be 8KL as you are really quite secluded from the rest.