How to describe Alto's Lament?

I'm singing it for a talent show in house assembly at school and I
don't know how exactly to explain the song as not everyone there will
be singers so may not necessarily understand it.

For anyone who hasn't heard the song it's
http://www.youtube.com/watch?v=oLBu4V-RLIE - my favourite version

http://www.youtube.com/watch?v=_cTuE0yvAdQfeature=related