As for your first question, I usually say go sequentially by order of how close they are. You don't want to force yourself on someone who isn't ready. Gosh, I hate being overwhelmed by lightening hands.
Now, however, there isn't a drastic difference in distance, I would suggest shaking the hand of the person in the middle, then to your left, and finish with your right. It looks kind of awkward to go down the line like you are a baseball player shaking hands with the opposing team, or something. Third question. Stay on your side of the table. These guys are professional and you should (hopefully) be standing while you shake hands, as will they. Unless it is a round table or giant table, then you should be able to reach across. If you can't, then walk around. Fourth question. Absolutely, shake to introduce, shake to depart. And I say take the initiative. Charge at them as if the handshake is your salvation. Don't make them come to you. Be a beast with the grip but don't break their arms.