Yes. You should make the connections in this order: 1) dead battery, positive terminal 2) live battery, positive terminal 3) live battery, negative terminal 4)

Yes. You should make the connections in this order: 1) dead battery, positive terminal 2) live battery, positive terminal 3) live battery, negative terminal 4) dead car, unpainted steel on engine block bolt/alternator housing/chassis/etc, as far from battery as practical. This works because the negative terminal of the battery is the chassis ground anyway. When disconnecting, break the connections in reverse order. Lead-acid batteries release hydrogen during discharge (and may vent it if the discharge is rapid), or from overcharging (water can electrolyze). So the live battery is likely releasing some, and the dead battery might be if it's actually damaged and not charging properly. So making the final, sparking connection (or first disconnection) is safest using the negative/ground wire (no potential), on the dead vehicle (avoiding the definitely-discharging live battery), and some distance away from the dead battery (mostly aviding the possibly-outgassing dead battery). This minimizes your chance of the spark igniting a cloud of hydrogen gas and getting a fireball. And now that you know why the order is what it is, you'll probably be able to remember it :-)