My sense is that you get even finer grain if you shoot at a lower EI.(posted 8642 days ago)No, the film should not be pull or push processed. C 41 is just developed 'out' when it is processed.
On the scene with the light background, that depends on how you meter it. Generally, XP 2 has a nice exposure range and thus can handle that kind of thing, to a degree.
chris