Over the fall my youngest son, Gregory and I collected all four Heroica sets and had a lot of fun playing with them. Grognardia has a nice in depth review of the components and game.
The only thing he missed emphasizing in his review is that the Heroica components are basically dungeon tiles that you assemble in a wide variety of configurations. There are two types of "tiles". The rooms which are mostly built on a 6 by 6 plate and the corridors which are built on 2 by X plates. Both rooms and corridors use the 2 by 2 pieces with a single post on top to control movement and placement.
There is no reason why it can't be used to run a game of basic D&D if you and the kids want a more detailed game. In addition once you get how the corridors and rooms are built it is easy to rob your other lego sets to build your own custom pieces. Gregory built a half dozen new potions and items to put into the dungeon. When we finally got all four sets he even took the extra weapons and items and painted them when he saw me painting my miniatures.
RIP Jack Chick
40 minutes ago