Game : Vampire: Bloodlines (PC)
Why : Best voice acting in a game ever. Superb script, believable characters. Get the community patch though, some bugs in it.
Recommendation : If you love story driven games! Play through *NOT* as Malkavian, then play again as Malkavian. Malkavian is just awesome. It's also technically the first game built using the HL2 engine.
Game : Baldur's Gate II (PC)
Why : Story driven epic, top-down gameplay, an absolutely massive amount of content. Would have to be up there as one of the most content loaded SP games ever, all hand crafted.
Recommendation : Great story, great voice acting, great combat, tons of awesome loot, dragons, strongholds, tasteful romances, more loot. If you have never played a top-down game before this is definitely one to try.
Game : Eador- Masters of the Broken World
Why : Deep, tactical strategy game. I guess similar to HoMM.
Recommendation : If you like challenging strategy games then sure. Be warned this game can be hard!