Planescape:Torment
Bought it from the bargain bin. The setting sound very interesting, but I've never been a fan of interactive novels or movies, and I prefer more advanced combat than what P:T is said to offer. But it's on my play list and I may end up loving it once I give it a try,

Alpha Centauri. I won it in a giveaway, but I want to wait for Alien Crossfire.

Hmm, let me think...

Mass Effect 2 and 3
Grand Theft Auto 4
Metal Gear Solid: Peace Walker and Portable Ops
Pokémon Platinum and Soul Silver
Deus Ex: Human Revolution
Fallout: New Vegas
The Walking Dead

To name a few. I just haven't gotten around to playing a lot of stuff because I have a massive backlog.

If you remove PS:T (which I played) and Fallout 2 (which I don't own) that's a good start for my list. But if I also look at other posts, the following games I own can be added: Arcanum, Mass Effect, Gabriel Knight 1, Arkham Asylum, LA Noire, and, well, tons of others.

Huge backlog, not much time to play. I got a Nexus 7 a week ago, and I plan to have a go at adventure games and maybe RPG's on it. For now I'm playing Broken Sword 1.

Planescape Torment and Baldurs Gate 1+2
I've had these a while, I'm waiting until I have a good stretch of time to play them uninterrupted.

The Witcher 2
Bought it the same time as the first one, which took quite a while to finish. I wanted to take a break from the series before round two. Plus I've been waiting for a graphics upgrade so I can do it justice!

Mass Effect 3
Brand new, wrapped 360 copy. Maybe the day one DLC left a bad taste in my mouth or maybe the game got over-hyped for me in the year leading up to release. I finally bought a copy about 8 months after release but I still haven't unwrapped it.

KOTOR 2
Brand new, wrapped... Yes I'm bad. Again wanted to take a break from the series before enjoying the follow up. It's been about a year so I might have to play this soon!

The problem with a good RPG is that they demand (and deserve) a lot of time!

Witcher 2 no doubt. Loved the first one and have had the second one for a while already. Heck, I have even read both books that have been translated into English. Just haven't gotten around playing TW2 yet.

Tomb Raider 1,2,3

I have Neverwinter Nights: Diamond Edition, and besides creating a character and walking through 3 minutes of the tutorial part...haven't played it.

Also, there are a ton of games I have on Steam but haven't played yet...for instance, Cryostasis...

Oh, boy. Probably too many to name them all, but here are a few:

Fallout:New Vegas
Batman:Arkham Asylum
Batman:Arkham City
Vampire The Masquerade:Bloodlines
Master of Orion 2
Nexus:The Jupiter Incident
Metro 2033
Saints Row the Third
Fallout

Tons more that I've collected and not yet played, but these are a few that are generally mentioned with good reviews when people talk about games.

I've actually played all the games I own though for how long is a huge vaiable...
Vampire:bloodlines deserves more than the 2hours I've put into it for example

He listed many of them in our conversation. Bad translation, bad combat, poor quest design, repetitive middle chapters, etc. etc.

Wh-

Why in god's name have you not played these games? Ok, look. You're from Canada, right? The system is pretty good for supporting people who are in between jobs. I'm going to need you to quit your job and start playing these games. Kids? They've got to learn to fend for themselves eventually, right? Wife? Parents? In-laws? They're adults! They can take care of themselves! (And if not, again, social support systems.) Remember: "Absence makes the heart grow fonder." I'm pretty sure that means they'll all love you *more* when you return from your five week video game bender. That's how I read it, anyway.

There is no way this plan can go badly.

My first thought was what SimonG posted as I don't know if they are good if I haven't played them.

I've played everything at least once to see if it runs, other than some of the latest bundles where I usually get to those games in batches. For a game I know I will like but haven't actually played yet would be Super Street Fighter 4 Arcade Edition for 360 is still sealed in its case. I bought it as I saw it on clearance and knew I would get around to it someday after liking SF4.