From the TS on another thread.
I'm taking a short trip to Tokyo with an overnight to Kyoto and, possibly, a day trip to Hakone.
If it's a short trip, there's more than sufficient things to do in Tokyo. Leave Kyoto for another trip, as there's a lot to cover, and one day is not doing any justice to the city.
If you leave Kyoto out, you may be able to find time to do a day trip to Hakone.