Questions on the battery on the MWS Tier 1 "Stunt" Electronics Kit

I want to buy one of the MWS Tier 1 "Stunt" Electronics Kits. They have several options on the battery set up which complete looses me. Can I do just the simple 4 AAA set up or do I have to do the rechargeable battery set up?

If I do the rechargeable battery setup, What's the most basic rechargeable battery setup and what kind of charger do I use? What battery charger do I get?

The description underneath the listing explains which battery is included and a link to the appropriate charger for it.