Creative, but frustrating.
As the title states, the DGN is literally a graphic novel, placed on a UMD. You can "turn" pages by pressing the X button, or simply waiting the for game to change the page itself. The entire story is a recount of the events that took place in the first Metal Gear Solid game. For new Metal Gear Solid players, the story involving a legendary spy codenamed Solid Snake, infiltrating a fake nuclear arms disposal facility, and destroying a nuclear equipped,legged tank, called Metal Gear.
The game allows you to read through the entire story without any interaction at all, if you wish. The game is similar to a UMD movie that way. On the first boot up of the game, you will not be prompted to enter any main menus, or load any save files, and the game starts off at the first scene of the novel. If you decide you want to interact with the game, you can press square to pause the scene and look for hidden "memories" inside that particular scene. Once you've located the memory you can acquire that memory by putting your cursor over it and pressing X. This will add it to your memory bank, which brings us to the next mode MGS:DGN has to offer. The Memory Building mode is a large VR system of many memory cubes in floating space. Once you've acquired enough memories through the Graphic Novel/Simulation mode, you can link each of the memory cubes together. The memory cubes come in groups, and you can link every single memory cube to at least another one. Once you've finished a group, you can move onto the next one. This mode is quite creative,though a bit frustrating, because of the poorly designed controls and camera for this mode. Once you've linked many memories together however, you'll find that it is extremely difficult to a specific memory that you wish to view, unless it is in the initial grouping.
The Metal Gear Solid:Digital Graphic Novel is an interesting collector's item for Metal Gear fans, but it doesn't hold it's own as an individual game, and certainly not as a Metal Gear "Game". The DGN is certainly worth the money if you can find it in a bargain bin, but due to it's rarity, I doubt many people will ever get their hands on the game.