Umm... no, that's not D&D. D&D has been around way befor video games. It's the original RPG. Before then they only had stratagy games (like 'Risk'), a few group of guys thought it would be cool to play as heros of these armies, that led to ChainMail. Gary Gynax to the concept a bit futher and created D&D, a complete interactive adventure. The term D&D actually covers a broad varity of pen & paper RPGs, even more so now with the d20 system. They range from midevil fantasy to sci-fi to modern spirtual detective. Basic you have the players (self explanitory) and the GM who is the one in charge. The GM creates the story, playes the monsters and guilds you through the game, if D&D was a video game the GM would be the computer.
In D&D you have a whole lot more freedom than in any video game, say to have to fight an evil wizard who is tormenting a local town. You can gather town members to storm his fort, sneak in using stealth, even try to join him. You make the desitions on what to do, however there will be consequences. If you are a level 1 Rouge who desides to take on a Red Dragon by yourseld expect to be making a new character. Yes, that's right, unless you got a crap load of cash or a really good Cleric pal, you stay dead. Don't expect to be having hundreds of HP ethier, you start out with anywhere from 4 to 12 HP (depending on your class). Armor ids different than video game RPGs as well, insted of reducing damage they nullify it. Basicly the better armor you got, the harder it is for an enemy to hit you.
The magic system is VAST! Over 130 pages listing spells and spell description in the player's handbook, other books and suplement have more spells. The down side is that you'll never learn them all, there's a limit on how many you can learn, and the really powerful spells can only be learned by a few.
If you want to learn more about D&D just do a internet search, or check out your local hobby store, but if you do use the internet ignore the sites saying D&D is evil, they are the same people that say video games, music, and anything else teenagers like is evil too.
DDR is the best form of exercise money can buy.