Are you sure you cannot choose another focus area by using the 4-way
switch (whatever its real name is - the round button with four
arrows)? This is what I use on my D70s, which should not be very
different from the D50.

Certainly the focus area is not the right one by default (in any mode
in which you cannot change it, it should be either the central one, or
the one selected automatically by the camera for that particular
shot). Since it is always the right one, I would suggest that you have
inadvertently changed it from its default center position. Either my
suggestion above or, failing this, reading the manual should solve the
problem.