Hi Nisal,
Are you asking, "Do I have to believe in literal rebirth in order to become enlightened?" That was one of the first questions I asked, and also one I occasionally play with, just to see if I can find a new angle to it.
So I don't have any answers to that one, just a few thoughts.
Rebirth is mentioned in the definition of (mundane) Right View, as in "there is this world and the next", and "there are spontaneouly born beings", whatever that may mean. If I remember correctly, the wording includes the phrase "no doubt". So what is "doubt", exactly? Currently, I think doubt is the kind of constant, unproductive questioning along the lines of "am I right? Am I wrong? Are the commentaries right? Is my teacher right? Is Stephen Batchelor right? Are the scholar monks right? Is Daniel Ingram right? Are the materialists right?..." Seeing it this way, I managed to shift the question of whether rebirth is literally true away from a question of orthodox belief and towards a question of identifying with views and opinions. Why do I want to identify with this particular view on rebirth? And this leads to practical inquiry, and thus to progress on the path - at least this is what I hope it does

Does samsara exist? Well, do you think of samsara as a place? Ven. Thanissaro points out that it is useful to think of it as an activity, something we *do*. Our actions shape our experience. And I find this is a very practical understanding of kamma and samsara, encouraging inquiry ("how do I act? How does this influence my experience").
Oh, and the arrow parable. I've found it to be a very apt, profound, expression of the sense of urgency, as well as an interesting meditation instruction: when sitting, and say, pain develops, how do I approach it?
Cheers,
Florian