I think that a perfect world would be a world without crime or terrorism. I also think that it shouldn't have any natural disaster at all. I would still think that a natural eruption of a volcano. There could also be tropical storms but they wouldn't be nearly as devastating as they are today. There would be annual monsoons throughout the world becuase in many countries they are needed to provide water ant the right crop growing conditions. This is the basis of the perfect world in my opinion.
Everyone would also get their choice of an iPad or the latsest Android tablet. Then the world would have the same assets as far a technology goes. The school systems would also have iPads for all of their students. The school would have 2 wifi routers for each wing in the building one for teachers and a second for students. Administrators would be on a different network than the teachers and students. Then the school systems wouldn't have to worry about buying books for students anymore.
The army would also have iPads or Android tablets for all officers in the army. The officers would have specially produced iPads or Tablets with combat standard protection so the could use it as a bullet-proof sheild. They could deflect a .50 caliber round and it would barely leave a dent. So the memory of the tablet would still be intact. Then if they were making a speech and they heard a gunshot the could throw it up in front of them and they wouldn't die from the bullet.