Dwarf Fortress games are often passed on, and there are tales, horrible tales, of many such fortresses. In the dark corners of the Interwebs one often hears whispers of one such fortress, one which was known by the name of... Boatmurdered.
Must have windows software? The only software that is 'must-have' when working on a computer with windows installed is Damn Small Linux. Ok, Kanotix also works well:)