ESP12 - something very wrong

So firstly - the terminal keeps throwing back "undefined" when entering perfectly valid Javascript

Are you certain? The code you specified should echo 1 on the console.

the manual refers to the default speed being 9600. Well, either I'm going blind or mine is defaulting to 115k.

115200 baud rate. Probably info refers to AT commands to ESP8266-12*.

Thirdly the first examples you see relate to LED1 - but mine knows nothing about LED1.

No onboard LEDs that you are intended to control on ESP8266-12*. You can control the Wifi light. Pin varies from board to board. D2 from memory on the NodeMCU, which uses ESP8266-12E

Also - this - in the docs - is unrecognised. ESP8266.getFreeFlash()

You need to require the module.

var esp = require("ESP8266");
esp.getFreeFlash(); // returns the info you wanted