The 3rd Edition of Dungeons & Dragons is, like all its counterparts, an action-adventure fantasy role-playing game. In this game players take on the role of a hero that they create themselves and go on adventures as a group.
Characters are created by choosing a race, class, feats, and skills. Most classes rely on magic to some degree, since D&D is a game of high-fantasy, but more on that to come. There are eight races and eleven classes in the Player's Handbook, which with enough houserules and supplements is enough to cover some of the stuff that I would ever care to play.
Races grant racial features, which are minor perks that usually dont affect your overall character much, and often emphasize classes that dont make sense with the abilities they possess. This is alright, since D&D is not about power-gaming but role-playing, and players should base their character around a concept instead of mechanics. Its okay that elves favor the wizard class despite having absolutely no inherent talent towards it.
However, some races actually end up working really well with their class. For example, dwarves make really good fighters, which isnt a problem since fighters suck anyway.
Thats a really important element of 3rd Edition: many classes are more powerful than the others. I dont agree with games that contain balanced choices, as thats not realistic, and I like my games to have lots of realism and immersion. In stories magic is something to be feared, and in Dungeons & Dragons magic is power, so its only logical that spellcasters have the potential to be the most powerful characters in the entire game.
They suck at the start, which is why it is fortunate that D&D is a team game: the rest of the non-magical characters can carry you around throughout half the campaign, after which its easy to dominate the scene so its basically an advance payment on future services rendered.
That being said, fighters are a great class for new players. They dont have any class features and are only really useful for making routine melee attacks over and over again, so its simple, straightforward, and lets the player understand the basics of mundane weapon-combat. Good to start with before moving on to more powerful classes like the cleric or druid.
Other classes like the bard dont perform really well in any aspect when it comes to combat, but are instead great for players who prefer role-playing, since they focus more on Charisma and skills than anything else.
Skills are a refreshing addition to the game. 2nd Edition had non-weapon proficiencies, which always seemed few and far between, but also too narrow in focus. 3rd Edition maintains the tradition by having skills that are likewise useful for narrow/one application(s), but gives some classes theoretically more skills to play with.
Having lots-of-skills-but-little-skill-points prevents players from covering much of the list, which is great because that prevents players from just sitting there and "roll-playing". They'll either focus on a few skills that they can succeed at in ideal conditions, or spread themselves so thin that they cannot accomplish even easy tasks. I prefer either extreme since it will force the players to "Zork" puzzles until they manage to twist, push, pull, or whatever in the right sequence before they are able to crawl their way to success. Fun? Hell yeah, and its more immersive and realistic this way! After all, characters shouldnt be awesome at everything they do.
Being able to arbitrarily decide the outcome to a situation reinforces the fact that the DM is the ultimate authority in the game, but also adds a layer of mystery for the players. What fun is it for you to select an ability and have it work as written, all the time? Adventuring is a dangerous business and the party shouldnt be able to reasonably count on their ability to scale a wall just because their combined bonus is twice that of the Difficulty Class.
Feats are like custom perks that sometimes improve your characters capabilities in the game, but can also open up new and untested subsystems for you to figure out and commit to memory. Many feats are incredibly situational or provide seemingly useful benefits. This adds a layer of system mastery to the game that is frankly necessary to separate the casual players from the hardcore group. I mean, whats the fun if anyone can just pick any old feat and have it be worthwhile?
Spellcasting mostly relies on a subsystem that is more or less a reverse of weapon attacks: you declare a target, and they have to make a roll to resist the effect. Also, spellcasters only get a couple spells a day, which forces players to try and figure out in advance what spells they want out of a list of spells that they are stuck with throughout the entire game.
Wizards get more spells than slots, and like feats are often only useful in specific situations. I like this because it allows me to introduce puzzle elements that reward the player for picking the right spell during creation (and you cant change them out later), preparing it for the adventure, and managing to have it on hand at the right time.
Sorcerers on the other hand can cast a lot of spells, but get a much smaller amount, which forces them to plan even further in advance. This lack of flexibility is made up by their ability to cast any spell on the list in advance, so as long as they picked useful spells during creation then they're probably good to go.
3E D&D is a great game, with plenty of gritty realism, rules mastery, and option-traps to facilitate replayability as your group continually strives to create a functional character concept and overcome randomized traps/save-or-screw effects. It cant get any better than this.