I totally agree with the advice on Mt. Fuji. Naive first-time visitors always say that they want to see Mt. Fuji and the Ginza, probably because those are the two places they have heard of. But the Ginza is just an avenue of expensive stores and isn't worth a special trip unless you want to see it when it's closed off to traffic on weekends, and even then, it isn't nearly as lively as some other "street fair" type places.

Others have described the lack of any need to go all the way to Mt. Fuji. (I was in the area in June a couple of years ago, visiting a client whose headquarters are literally in the foothills of Mt. Fuji, and you wouldn't even know the mountain existed, the air was so hazy.) If the air is clear, the view from the north side of the train or from a tall building in Tokyo should do the trick. If the air isn't clear, you could be practically on the mountain and not see it.