I think before deciding whether or not you should take the 5 year old to see The Mikado, you should tell them the story. I don't think you should take someone that young to see a show without first talking about what it's about and who the characters are and the funny things that happen in the show... maybe even play some of the songs for him/her and explain what the songs are about. That way, when you do go, there is already a familiarity with the show for the child.
They will enjoy it more because they will understand it. In telling the child about the Mikado and making it sound exciting and fun and making it understandable, you'll be able to see if they have an interest in going to see it live. My Mom started introducing me to Gilbert and Sullivan at around that age and by second grade, I was a huge fan.
So there isn't really a clear cut yes or no answer to whether or not it is suitable to take a 5 year old to see it. It depends on the five year old and how you prepare them for ... more.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.