You dont need to read the whole thing, there are seperate sections relating to the different issues you are asking about.
2 + 2 = 4. Series doubled the voltage, parallel doubles the mah.
You will need:
A UBEC / BEC.
A capacitor equal to 25v 105*C low esr 2000-4000uf.
A series Y-harness for the 2x 2s lipos to be wired together IN SERIES.
Yes, you are stupid, now go away before I fart on your head.
If you skip to the lipo tutorial, it explains what you need to do, as does the BL upgrade section in the FAQs.
Its all good...