Basically we learned that Japan was unified under the Shogun and then completely isolated itself.

That's actually not very accurate itself. Their official political stance was one of isolation from the outside world, but people knew about Japan and some specifically ordained Japanese people had intercourse with foreigners. The basic example is the Dutch outpost at Deshima maintained the entire time, but the Satsuma clan frequently came into contact with foreign countries by circumventing the exclusion laws through their nebulous control of the Kingdom of Okinawa. In fact, Western countries, on their spree of Asian colonization, spent a good half century both trying to open the ports of Japan the legal commerce and attacking the "Okinawa problem," which was all about the legal status of the relationship of Japan and China to Okinawa, which was used by both governments as a point of contention between the two in order to achieve political goals, much like the Senkaku Islands are now.

It was then this unchanging place for hundreds of years until Commodore Perry opened Japan.

Also not really accurate, but most of what was "happening" was internal politics--much like any other country, and thus of varying interest. There were some technical advancements, and some consider the period to be a very long and slow shift of the social order that seems static from the outside, akin to accumulating snow on a mountaintop before the final push turned it into an avalanche that was the Meiji Restoration.

The dominant global narrative of Japan at the time is the one you mention in your original post, and it suffices if you want to tell "the story of the world" in a form you could possibly finish in a reasonable time frame, but much like any other group of people, you can dig down and find a lot of interesting stuff.