In most likelihood there will be no effect at all to people in Tokyo, but you still worry with young kids and soon to be born ones!
On the news they said that radioactivity levels in Tokyo were 24 times higher than normal. But that it is still much, much less than a harmful level to humans. Still, i prefer not to take chances.
So the wife and son are heading off with her parents out of Tokyo.
As you cant get water in the supermarkets i have stocked up on beer and cocktail drinks, as i heard they have some protective powers against radiation. Especially if drunk in large quantities. No wife, no son and a lot of alcohol... the next few days should be fun!