You want the batteries hooked up in series for 4s. Some esc's don't come with any battery connectors installed, some have a single battery connector, others have 2 battery connectors already setup in series. Pick the esc you want then solder on the battery connectors so you don't have to use any adapters.

Edit: As far as recommendations for which esc and motor, I try to steer people away from Turnigy Trackstar. The Hobbywing Max8 Funniekid linked to is about $50 more but they are proven to be more reliable, the esc is 6s 150amp capable instead of 4s 120amp, the esc is smoother, according to the pics it already has 2 battery connectors setup in series, it's just a better system.