I would agree with the right side. The BA approach to LAX usually comes from direct east, so if you're on the right side you can see Downtown LA, the Hollywood sign, Griffith Observatory, the Santa Monica Mountains (besides these things not much to see but freeways and urban sprawl). Sometimes the approach might be from the north and the 747 will do a detour around Downtown LA before lining up for the approach from the east, in this situation the right side is still better in my opinion. Have a good trip to LA!