That sort of screw type bananas are simple to put together, but they don't necessarly stay tight. All you need is a screw driver for those.
That sub cable looks a little cheap, but it should work fine.
I am not a fan of flat cable, but as long as it is the correct AWG for how long you are going to run, it should be OK. That means at least 14AWG. You don't need anything special in terms of wire if it isn't going to be run inside the wall.