For a nice game of Dungeons & Dragons play Dungeon Robber. This is played in the browser using Flash.
The dungeon is generated every move you make and you see what the game is doing by a map that is visible in the left. Not a map of the dungeon, but a map of the generating process.
Develop the town by retiring with enough experience points. New options come available, so that you can play as thief, buy thing at the smith, etcetera.