Hi,
I went to Iceland last October as part of my sixth form studies. If there is one place in the world you have to go, I would suggest there. Apart from the obvious geological value, it has some of the most beautiful sites around, and on most nights, depending where you are, you can see the aurora borealis A.K.A Northern lights, and believe me, they are a once in a liftime sight.
I also went snowmobilling on top of Iceland's biggest Ice Cap. It was amazing until we were told about us actually going many metres away from a volcanoe which erupted not long ago, i think a small one happened last year.
Its quite cute that all Icelanders believe in the 'little people'. These are the equivelant of trolls who look after every rock and tree etc. The country even go to extreme's. You are not allowed planning permission where there is thought to be trolls. So as you drive around reykjavik you see many unused plots where there are a mass abundance of rocks, thought to be 'Little Homes'
I would suggest everyone goes, even if you don't do geology, I will probably go again later in life. But one thing that detered me was prices. Not of flights or hotels but general goods. I.E. a pint over there costs £4, a bottle of coke, small, is £1.50 upwards.
I would suggest staying in reykjavik for one night then travel along highway 1 anti clockwise around the country - - ABSOLUTELY AMAZING!!