in a crash, especially with another mobile or immobile object, frame material has absolutely nothing to do with it's survivability.
wrong (as is often the case when the word "absolutely" is used in statements) for reasons already mentioned.
to the OP - i second the vote for Ti, with Alu being a good second choice for a bike that will last for a good while. steel is good, but if you rough it up over time and dont stay on top of it, rust can be a long term problem.