Photoshop is best for texture packs by far. But if you cant afford it, Gimps free and it works well too.
Quicktime is OK for recording, I personally use camtaisa studio, That ones good.
I've been hearing that OBS is great!, If you can figure out how to use it
Imovie is GREAT for editing that either comes with the mac, or you buy it from the apple store.
I got mine with garageband and IMovie pre-installed...