Tabletop or pen-and-paper RPGs actually began as "wargames", where you would control armies to simulate large-scale battles. They evolved quite fast, and were soon revolutionized thanks to Dungeons & Dragons, which was one of the first, maybe THE first, were instead of an army you would control individual characters, picking up it's race and class then rolling it's status. D&D quickly became a huge hit and also a huge cash cow, and like all cash cows it also got tons of licensed stuff, which obviously included videogames.
A Zelda-like action-RPG set in the Arabian Nights-themed Al-Qadim D&D setting, with a great story and satisfying combat and puzzles.
You control a party of six characters, each with their own extensive personalities. If you carry both Good and Evil NPCs in the same group, or if you heckle them, they will often leave or try to kill you/each other. High charisma generally avoids more extreme reactions, however.
D&D rules are in effect, giving you the option to choose from almost any fantasy class or multi-class. A pause feature allows for perfect management of the characters in your control.
Windows, Mac, iOS, Android
Chronicles of Mystara
Beat 'em Up
Classic arcade beat 'em ups with tons of depth. Further expanded on the RPG fusion by incorporating an inventory, magick and multiple paths through the high fantasy realms of D&D. Tower of Doom features up to four players and four different characters, but you can't change your character upon dying/continuing or have more than one of each. Shadow of Mystara features two new characters (a male Wizard and female Thief), alternate skins, more branching pathways (some even needing a certain character to access like dwarf or elf), more magic items (like elemental-summoning items) and magic weapons (like fire sword and morning-star), and tons of secrets which add to its replayability.
Arcade, Windows, PS3, Xbox 360
Eye of the Beholder
Great first-person dungeon crawler inspired by Dungeon Master, with seamless combat where you can attack enemies from a distance as soon as they're visible, adding strategy to the otherwise simple combat system. Has two sequels, The Legend of Darkmoon and Assault on Myth Drannor, which streamline elements and brings better graphics, as well as allowing importing parties from the previous games. Myth Drannor is the weakest title and not really worth playing outside of curiosity.
MS-DOS, Amiga, SNES, PC-98
Another series of Infinity Engine RPGs based on D&D. They play much like Baldur's Gate, but focusing less on story and memorable characters and more on combat, exploration and dungeon-crawling, being great for novices wanting something more accessible and for veterans looking for a good challenge!
Unlike the classical CRPGs from Black Isle the gameplay is a bit different: You only play one character and (depending on the add-on) have either one or two sidekicks. But just like Baldur's Gate you have a gazillion possibilities when it comes to character customization (Classes, races, skils, feats, weapons, spells, you name it!). The story of the main game is your standard run-of-the-mill fantasy story, but the (interconnected) story of the first and second add-on really shine! There's also a ton of decent free campaigns (Check out Darkness over Daggerfold made by a team featuring the producer from the Baldur's Gate add-on Throne of Bhaal!) and some decent paid DLC campaigns (premium modules). Since they stopped selling these they also deactivated the license check, so you can play them for free, and the Diamond Version from GOG.com comes with 2 of these premium modules.
Windows, Linux, Mac
Widely regarded as THE BEST RPG ever made. This is a very dark, story driven game. D&D rules are present, using the Planescape setting, with an amazing multiverse world where Good verse Evil blended with Law verse Chaos: featuring philosophy, existentialism, demons, angels, order and chaos beings, etc. Although this game focuses more on the RPG/dialogue part and a bit less on the Action/Combat, the combat sections are still awesome, featuring even "cutscene spells" ala FF summons. Features a wide varied cast of colorful and unique companions even for a D&D adventure. The music, writing and story in this game are objectively THE BEST of any other RPG. Period.
SSI's "Gold Box" series
The Gold Box series (nicknamed as such by fans due to their golden-colored boxes) were the first officially licensed D&D RPGs, aiming to faithfully adapt the D&D rules. They all play very similarly, with exploration being done on an overhead map with first-person dungeons while battles are fought on a top-down isometric field in a tactical turn-based system. The series features dozens of games divided into several sagas, allowing players to transfer their party between games of the same saga.
The Pools saga (Pool of Radiance/Curse of the Azure Bonds/Secret of the Silver Blade/Pools of Darkness) were the first titles in the series, set in the Forgotten Realms setting, and may look dated now (especially the first three titles, which still used EGA graphics) but are still great titles. The Krynn saga (Champions of Krynn/Death knights of Krynn/Dark Queen of Krynn) moves to the Dragonlance setting and are some of the most popular of the entire Gold Box games. The Savage Frontier saga (Gateway to the Savage Frontier/Treasures of the Savage Frontier) goes back to the Forgotten Realms setting and improves on a lot of the mechanics and offers a good difficulty curve, being great entry points for beginners. The series conclude with the Dark Sun saga (Shattered Lands/Wake of the Ravager), which are set on the titular Dark Sun setting and bring a much improved interface and visuals but are plagued with bugs.