Don't shoot it with the arrow? I met some bizzare and repeatable crash conditions during the opening quest as well, for instance that bridge that the rocks take out once you and whoever are across it? Unless I let the NPC get across the bridge first I'd hit a CTD consistently, so I just let the NPC cross first. So in your case: Try engaging the bear without a bow and see how that goes. (I can shoot the bear just fine with a bow but who knows, any ways experimentation is key)