I'd recommend catching up on older, proven games you might not have played before. Looking through the old games available on Steam or GoG.com, I'd suggest...
The Baldur's Gate series
Planescape: Torment
X-COM: UFO Defense
Any of the old LucasArts adventure games (Monkey Island, Indiana Jones, The Dig...)
Half-Life and Expansions (I freaking LOVED Opposing Force)
Shining Force 2 (originally on Sega Genesis, you can get it on Steam for PC)
Dark Forces 2: Jedi Knight
The Baldur's Gate series
Planescape: Torment
X-COM: UFO Defense
Any of the old LucasArts adventure games (Monkey Island, Indiana Jones, The Dig...)
Half-Life and Expansions (I freaking LOVED Opposing Force)
Shining Force 2 (originally on Sega Genesis, you can get it on Steam for PC)
Dark Forces 2: Jedi Knight