One most likely would call Icewind Dale a "Hack-n-Slash" game. Compared to its cousins Baldur's Gate 1 and 2, Icewind Dale certainly has more focus on fighting, more enemies, more obstacles which you have to "hack" your way through. That isn't to imply at all that Icewind Dale is a game lacking in depth. While it does have a large amount of combat, if you're thirsting for a deep, engaging adventure, full of exploring, talking, and other things like that, Icewind Dale will fill that for you as well.
If you've played games like Baldur's Gate 1 and 2 in the past, you have a pretty good idea what to expect from Icewind Dale, as it plays similar in style to both of those games. In Icewind Dale, at the start you create your initial party of six. You have choices of the usual range of characters, being able to make a Dwarven Thief and a Elven Ranger live in harmony. You have full control over the creation of your characters, from the gender and appearance, to the alignment and ability. They also have a number of pre-generated characters, which are nice if you're not sure what to pick. Obviously though, it's much more fun to make them yourself. Once you've finished making your party, the game will begin.
Once you're done with the character creation, you're presented with a brief introduction to the story, and then you'll find yourself inside of an inn. A man will come up to you and enter into a conversation. Conversations consist of a series of discussions, with choices in between. At breaks in the conversation, you'll often be presented with different topics which you can choose to continue with, which will grant you different paths and information from the discussions.
Once you're finished talking to him, you're free to explore the inn, and talk to the people inside. You have control over your entire party of six, being able to move each of them individually, or issue commands as a group. You can easily select everyone in your group by pressing the = key. Aside from that, you can drag a box around the characters you want control over, or select them individually by clicking on them. You can then issue commands to your selected people, to move to a particular point, to talk, or to attack.
Inside of the inn, you'll soon come to your first task. The barmaid will tell you that there are bugs in the cellar, and that she can't get any ale until they're cleared out (oh no! The other people in the bar aren't likely to be too happy about that). So, you offer to help out, and head down to the cellar. Once you take care of all of them, you head back up the stairs to talk with her again. She'll thank you for your help, she'll reward you with some gold, and you'll gain some experience.
This is how much of the game progresses, with you getting various tasks to do, going out to accomplish them, and then getting a reward at the end. It isn't one long fetch-quest though, many of the quests just lead you along to where you need to go next so that you're not wandering around lost with nothing to do. Quests aren't the only way to increase your characters. As you fight enemies, you'll gain experience, which will eventually lead to your level increasing. When this happens, you'll gain in stats and sometimes be given the opportunity to increase in some of your skills.
Again, much of this probably seems familiar if you've played either of the Baldur's Gate games, and even if you haven't it doesn't take too long to pick up on. The fighting is fairly straightforward, with you moving your people and group around, and when enemies appear attacking them by weapons, or spells, or whatever means necessary. Battle takes place in "real-time," in that both you and your enemies are right out on there on the map screen fighting back and forth (the core of the battle is still based on the base of dice-rolls and statistics juggling, but as all this is being handled on the fly by the computer, you don't need to pay much attention to this if you're not interested). You can pause the game at any time however, and can also set the game options to have it automatically pause under certain circumstances (such as when you're attacked, when you defeat an enemy, when one of your weapons are unusable, if one of your characters die, or other such situations), which can provide breaks in the action to give more of a turn-based feel to it. That's entirely up to you though, however you feel comfortable playing.
The game itself is located in the Forgotten Realms. Again, this land may well be familiar to you, not only if you've played Baldur's Gate, but many of the other games and situations centered in this D&D land. Your journey will find you going from the starting town of Easthaven, to places such as Kuldahar, the Vale of Shadows, and other places in the surrounding area. You'll trek through open fields, dark caves, snowy peaks, and many other areas. Your journey will take you through a wide variety of places, each with different enemies to encounter, places to explore, and things to do.
As was mentioned at the outset, if one wants to place Icewind Dale into a category, one would most likely call it a "Hack-n-Slash" game. Compared to the similar Baldur's Gate games, there certainly is much more fighting in Icewind Dale than there is in either of those games. That isn't to say the game is devoid of quest or interaction however. You still have large towns to visit, building to explore, people to talk with, and quests to complete. While you will have to go through many enemies along the way, Icewind Dale is far from all fighting and nothing else, there is a number of other things going on. If you're not interested in all the other stuff, you will have a bit of a difficult time making your way through the game, as you do need to pay some attention to what is going on around you. If you are just looking for a straight Hack-n-Slash though, while it is more complex than that, if it's what you're looking for, it's not too bad for that either. Nonetheless, the game really is an excellent mix of action and exploring, rolled into one.
As far as graphics go, Icewind Dale does look very pretty. While most of the land is static and you only get one camera angle, everything around you looks very nice and there's a wide variety to the land you'll explore. The monsters and other moving things you come across throughout the game also look very good. The sound in the game isn't all that oppressive where you're going to be noticing it all the time, but it always sounds very nice, and sets the mood for the game well.
The main quest itself is fairly long, probably around 20 hours depending on how much time you spend exploring and doing side things. To explore and do everything there is to do, 40 hours is probably a good general idea, although it can vary. Once you've beaten the game, and even after you've seen everything there is to see, there are still plenty of reasons to play through the game. The character creation system is very good, and with the wide variety of character possibilities and the six person party, trying out different people and combinations can give a very different look to the game. Playing through with a group of Fighters and Paladins, as opposed to Bards, Druids and Mages gives a very different look and feel to the game. Even if you aren't as interested in trying out all the different combinations and just want to stick with a group you know works well for you, it's still a very enjoyable game to play through, wandering around and exploring and doing all there is to do.
Icewind Dale may be a few years old at this point, and certainly other games have come along that are very fun as well. This game still holds up very well through time however, and if you're looking for a nice mix of action and questing, fighting and exploring, this is still one of the best games out there.