What's the difference between "Dungeons & Dragons Board Game" and the "Dungeons and Dragons" game?

I would say that you have the basic idea of the differences. D&D board games would be a preset game type with preset characters. AD&D (Advanced Dungeons and Dragons) Is very free form with a person or persons who are the dungeon master (DM.) this is very in-depth, but takes lots of imagination and not easily picked up. Being a new DM is very difficult, the hardest part of playing AD&D, but you can buy pre-prepared adventures to get started. AD&D is a ton of fun and can be very fulfilling if you put the time into it. Hope that helps.

The board game has a limited story, the role-playing game (rpg) is not limited in any way. Since you have played the board game you understand what it is all about. I will explain what happens in the rpg. First there are more locations, as many as the Dungeon Master (DM)wants to include. The DM many have already mapped them out, but sometimes, they may just be necessary so they are invented on the fly based on the imagination and real life experience of the DM. In the rpg, the details about your character can be quite complete. I have my players create a family complete with siblings and occupations. In the rpg you can encounter the mythic gods including Thor and Odin or Zues and Hecate. The story in a rpg can be as realistic or as fantastic as you want it to be. You can have an adventure in a floating cloud castle or inside an active volcano. You can leave the confines of the prime material plane and visit the Abyss or the Seven Heavens, a plane of fire or one of water. Truely the rpg has very little limits. In the rpg you can start a character as a teenager and have them live hundreds of years while going on thousands of adventures. (It would take a lot of dedication to do that, but I am certain that some body had gotten that into the game.) And here is the bid difference, as long as your character lives, the game never ends. You are just waiting to go on the next big adventure. The rules for adventure in the rpg cover just about everything from basic existence on a prime material plane to dealing with unique forms such as etheral or astral. What I am trying to say is that if you and your friends put the effort into playing Dungeons and Dragons rpg then you can have as much fun as you like and only your imaginations will limit the action.

Instead of going with a strict definition, let's go instead with what would you like to play? In the strictest definition, yes, Dungeons & Dragons is an RPG (Role Playing Game). However, its origins are in miniatures warfare, and that is reflected in the very tactical nature of dungeon-delving with the Dungeon Master carefully planning out maps on graph paper, through which the players move, aided by miniatures of their characters, the monsters they encounter, and so on. The latest (4th) edition of Dungeons and Dragons is becoming more and more of a board/miniatures type of game again. If what you're looking for is an RPG, then there are better choices, like White Wolf's World of Darkness, or even some of the excellent free online products like Fudge or Fate. For a more boardgame-style experience, have a look at Ravenloft or Descent. Both are way WAY better at accomplishing dungeon-delving with a board than the game you mention (and Ravenloft is part of the D&D franchise).