Get to Mt Fuji from Hakone?

Hi - we're staying in Hakone for 3 days and wanted advice on what to do. I dont want to book a tour from the UK as i'm sure we can find our way up Fuji etc when we're out there - or am I unrealistic? How easy is it to get to Mt Fuji and what other key things can we do in and around the Hakone area for 3 days? thanks! Also any advice on what to do in Takayama for 3 days - is it worth extending to 4 days to catch the Autumn festival or will we be bored for that long?? Thanks!!

How to get from Hakone to the Fuji Five Lakes at the base of Mount Fuji (is that where you want to go when refering to "Mt Fuji"?):
http://www.japan-guide.com/e/e6905.html?aFROM=5200_6900

we're staying in Hakone for 3 days and wanted advice on what to do.

Some ideas:
http://www.japan-guide.com/e/e5200.html

Also any advice on what to do in Takayama for 3 days

Here you go:
http://www.japan-guide.com/e/e5900.html

is it worth extending to 4 days to catch the Autumn festival or will we be bored for that long??

Three days is enough time to see Takayama in detail. But if you could still find a hotel room for the festival, it would be worth extending your stay for the festival.