RE: NEW TO ELECTRIC ( wanting to convert to electreic)
Jeff,
I use a separate battery to run my RX and servos instead of a BEC. If you want to run a 2S lipo to run your RX and servos you will need a regulator, and I would suggest one with a failsafe switch.
An electric motor is just like a glow engine for all intense and purposes in that it puts power to the prop. If a 14" prop is too big you can always go to a smaller prop with more pitch. The nice thing about an electric is you can put a watt meter on it and see if the prop choice is too much load.
Now for your battery and ESC quandary, the motor will have a suggested cell count range and maximum amperage draw. Once you know that getting what you need is pretty easy. I have an Ultimate bipe that is slated for a conversion. the motor I bought for it is 70 amp max draw and will run 5S so I will use half of my pattern packs (5s 4000mah pack) to run it. The reason for the high mah in my application is that I have them and won't need to buy yet another pack for this plane.
I hope that helped clear up some things for you.
Pete