This list includes experiences and info. And in RANDOM Order.
1. Skyrim - Dovahkiin awaits your PC. Play as Dragonborn and create your own story in Skyrim. Or maybe, Just become a Werewolf and Kill everyone in Rorikstead. (A Village.)
2. Star Wars: The Old Republic - Want a MMO that is on Space and made by the team that Made Knights of the Old Republic? Then Give this one a Try! Races and Classes from the movie appears, and a cool storyline that can pull you in the Dark Side, or in the Force.
3. Minecraft - Sandbox. Best Online Sandbox ever.
4. Mass Effect 2 - Follow Shepard's adventure with the Crew. and Normandy.
5. Team Fortress 2 - Its free. Fun Shooter made by Valve.
6. Diablo 2 - Definitely a must.
7. Starcraft 2 - Awesome RTS.
8. Neverwinter Nights
9. Baldur's Gate 2 - Even this is old, This game will really give you the spirit of adventure.
10. Fallout 3 - Post-Apocalyptic adventure. Approved.
11. NBA 2k12- If you want to see your Player dunk, play this.
12. Gothic 2 GOLD EDITION - The Best in it's Series.
13. Portal
14. Dragon Age: Origins (Not Dragon Age: 2)
15. Civ 5
16. Crysis
17. GTA 4
18. Battlefield 3
There you go.