D&D Tactics is not a flashy title, but it is a very deep tactical RPG for fans of pen & paper RPGs.
If you love Dungeons and Dragons in its table-top pen-and-paper form, then you'll also be pleased with this title, as it keeps much of the character creation and development depth, and uses the AD&D rules to carry out combat (with a little bit of simplification).
There is a story in the main game's campaign, though it is there really just as a skeleton framework to tie together individual skirmishes. You won't be buying this title for the story (or if you do, you won't be happy...).
As for the game's battles, they can range anywhere from quite easy and straightforward to quite long and challenging.
Visuals: The visuals are decent pseudo-3d isometric, with a freely rotatable camera. Characters on screen have a medium level of detail, but doesn't really show your character's particular equipment, etc, and has limited customization options. Character animations are fluid, though limited to walking/running and hacking. Things are so small on screen that it's sometimes hard to tell which weapon you're wielding, though you won't rely on the visuals for that -- you'll use the various menus during combat to assess what's going on. Some of the story mode artwork is very well done, with the classic "big character portraits over typed dialog" approach you see in many Japanese SRPGs.
Audio: The audio is largely forgettable, with a basic set of orchestral tunes. There is no spoken dialog, and sound effects are very odd and sparse.
Gameplay: Battles are purely turn-based, allowing you a certain number of actions per character per turn, showing the order of the queue of participants based on dexterity, initiative rolls, etc. You will need to use a great deal of strategy in these battles, as they can get very difficult very quickly if you don't manage them well. You can save at any time, which is great for a portable title, also letting you save frequently during tough battles as you get past each key point in a battle (or to backtrack just a little if you mess up...).
Overall it's a solid strategy/tactical title that's great for people that love DEEP strategy RPGs. Those looking for something lighter weight, or with more emphasis on the campaign/story, should probably look elsewhere.