This is the second time I have visited this castle, the first was about 10 years ago. While it is a reconstruction (rebuilt around the 60's) it has a lot of history. Unfortunately, if you don't read Japanese, don't expect to understand a lot of what went on. This is probably one of the only attractions I have been to where there has been little or no attempt to attach english explanations. Over the past few years many of the attractions of cultural importance that I have visited have gone out of their way to add explanations in english (some in Chinese and Korean as well). They may not be extensive but they do try and address the foreign visitors coming to their attractions. If you do visit this attraction and your knowledge of Japanese is limited, make sure you read up on it and its strategic importance in History.
The cost of Yen 500 will give you good views from the 4th and 5th floor and a walk though a reconstructed castle with lots of exhibition with japanese only explanations.