Hi CF,
While I do believe that Christ was the fulfillment of the law and his teachings and Paul's exegesis on the OT (which I believe was inspired) formed the basis for a revelatory new understanding of God, I agree that what many Christians think Jews believed (and still do) is not correct and we shouldn't presume. In fact, I think the best way to get back to first century Christianity is to start with a first century Jewish mindset and understanding and proceed from there. Too much Platonism and other heathen ideas have been inserted into the scriptures and the perceived thinking of first century Christians.
I am curious though, what do you think the purpose of the Eden story was with the judgements issued? It seems that death was not an option before the disobedience and now we all die, regardless of whether or not we inherit an original sin or not. We somehow inherit death, as it seems to indicate, at least on the surface. I am sincerely interested in your thoughts, so please do not let any presumptuous people get you too upset. I welcome other thoughts and especially those of learned Jews.