I think this actually was the first PC game that I have ever played (well apart from those pre-installed games on Windows XP like Solitaire). I enjoyed it back in the days. I still do.
Disciples II is a turn-based strategy game with beautiful graphics (even for today) and rich storyline. Unlike other turn-based strategy titles like Heroes, the battle system offers a control over individual units instead of stacked units, which I find very convenient. Also the different strategies you can use to complete a map and the rich storyline guarantees that the gameplay does not get repetitive as it is with Heroes of Might and Magic.
In Disciples II, you get to choose from five different races (Elves, Humans, Dwarfes, Demons and Undeads) with their own unique agendas and characteristics. Also you can choose one of three classes for yourself as a strategist: Mage (cast spells twice a day), Warlord (restore Health more quickly) or Guildmaster (more resources and actions for the Thief). So when you've completed game with one race/leader class you can try another.
This game offers three elements of gaming experience that I value the most: great style, rich storyline and character development/customization. Also, this game rewards exploring and there are plenty of quest maps to try after the campaign mode is complete.
What I didn't like about this game however was that you can export only one leader and only five items to the next campaign, so lot of valuable equipment is lost in the process. Also I didn't like that only a particular development branch could be chosen for a unit class instead of them all. Also, the Multiplayer via Directplay does not work anymore. I guess, you need to try external services like GameRanger for that.
Nevertheless, Disciples II is a great classic turn-based strategy game. My overall rating is 10/10.
p.s. Don't believe other reviews. This game works on Windows 8.1 like a charm. I had some issues with fullscreen on my laptop (I had to choose a lower resolution, otherwise the game won't fit the screen), but with external monitor there are no problems at all.