Basically what Baal said. You're a young king, who discovers the magic of architek, and you have to rebuild the kingdom. You recruit adventurers to go out to dungeons to find elementite (the material needed to use architek), while you stay in the kingdom, raise the morale of the people, and build new structures.
Like I said, it's pretty good, for WiiWare. I wouldn't ever buy it if it came with a $50 price tag.