well why don't you just go see if there are any other missions to do, if you've done them all and all that remains is the zero missions, then you are stuck with the stupid planes.
I agree though, I HATE the zero missions, I got a little farther in the game when I had it for PS2 and I believe you can just not do those missions, because I got to Los Venturas and then stop becuase I waited for the xbox version so I'm right about to get back to Los Venturas.