It is only recently that I saw a row of icons (users' avatars) and captions near the bottom of the screen referring to other supposedly related threads that may be clicked on. We could call them "featured threads" just waiting for a reply.
When you back your car up a high level of responsibility is put upon you.
Technically, you sue the other party, not his insurance company. His insurance company has the obligation of defending the suit and paying any judgment against you up to the limits of the policy. For convenience it is customary to bring a claim against the other party's insurance prior to giving the other party the details or filing anything in court.