Looks root bound. It was probably a container tree and who ever planted it didn't root prune it when it was planted. So the roots continued to go around in circles. You can still root prune it but it will be hard on one that size. What you need to do is somehow cut the roots in a strait line starting as close to the trunk as you can strait down and strait out from the trunk outward. I would do it in 3 spots equally spaced out. It would be helpful to pre soak the ground so digging will be easier. Make sure you do a utility check before you dig. I planted thousands of trees in yards and a lot of them were very close to utility lines.
You might sacrifice a chainsaw blade and just cut the roots dirt and all. It gonna destroy the chain and maybe the bar as well. If you have some old chains and old bar, use that. I keep old bars and chains just for these kind of jobs.
As for the spots on the leaves, it looks like sunburn after a rain. I'll bet it's just on the outer leaves and not on the inner leaves.
