wanted to suggest super meat boy :DDD
well, The binding of Isaac i think would be nice too

Thats a good list, have fun :)
Me? I need to finish Skyrim.

Rofl TF2? Cya next year. :p

Dead Space isn't scary -_-
Definitely worth going for Portal 1&2
Oh, and GL with 100%ing tf2. The Youtube achievements for it are just BS. Although you might be able to do it if you've got a popular enough youtube channel or something.

i have only 100%'d skyrim sadly, and that took forever due to a glitch D:

Out of the PC I would recommend you to play any zelda game, ocarina of time is the most recommended.
For the pc i recommend the original Mass Effect.

Portal 1/2 They are pretty easy to get and also fun. I can help you with co-op if necessary ^^
EDIT: Saw that you added those already. Sonic Generations might also be a nice choice, but it has collectibles.

Gmod, hohoho!

Psychonauts!

Ninja reflex, go go :D Some of the achieves are pretty... HARD :D
And psychonauts are pretty easy, i got all achieves in 30-40 hours :D

Cave Story+, I finally beat it on the best ending two days ago

Sequence and Zeno Clash have both easy 100%. These are only 100% i have, if you need help with any achievement in these games, just PM me :)

I'd say Fallout: NV, but it's not exactly possible with a single playthrough. You need to do a before-final-decision save, and take different paths from that. And, well, I've 88 hrs in and still haven't finished the game. Though you can do it much faster if you skip exploring and sidekick quests.

Just a tip for Bastion. The dreams with all shrine idols invoked can be quite hard. You might die at the last wave and be forced to do it all over again. So, first of all, be patient. :D The best weapon combination I've seen for that is the Galleon Mortar and the Brusher's Pike. The mortar is extremely effective when used with dodging, and with all the upgrades, it can kill most enemies with one shot. The blast radius is also a plus.

Oh, and for Shogun 2, good luck with "There Can Be Only One: Achieve the ultimate accolade and obtain rank 1 on the multiplayer Shogun Ladder."

Scratch that, do Universe Sandbox. I'd love to see you play that for a full year.

The only game I currently have 100% achievements is Stacking. I'm currently working on getting them all in Skyrim.

here are some that i did you might want to check out:

• aquaria
• on the rain-slick precipice of darkness, episode two
• toki tori
• trine
• trine 2

* Secret of the magic crystals

• And Yet It Moves
• Dungeons of Dredmor
• Borderlands
• Mount & Blade
• Portal
• Realm of the mad God
• Serious Sam 3: BFE
  This is all that comes to mind right now!

limbo.. i just miss one on my xbox360. supermeat boy.... good luck with both, there are some pretty bad ass cheevo on them :D

Get the Half Life 2 achievements that you missed and try to do Lucid :P. It took me about 5 hours.

I got 100% also on Rochard, The wonderful end of the world, Eversion and Dystopia.

1... 2... 3... Kick It (there's only one, and it's not that hard)
Defense Grid: The Awakening (to get 100% on it now, you need to also own the "You Monster" Portal-themed DLC though)
Flight Control HD (should definitely be doable)
Gravitron 2 (might not be too bad)
+1 to the Half-Life 2 suggestion (they're mostly reasonable)
+1 to Limbo (definitely doable, and satisfying; might need hints on egg positions)
Monkey Island 2: Special Edition (they're all hidden!!! :D lol...)
Plants Vs. Zombies (tough, but mostly enjoyable)
+1 to Portal/Portal 2
RUSH (...might drive you nuts)
The Wonderful End of the World (easy... ish)

What about create YT Channel just about you, playing Super Meat Boy? I will be better than Rage Quit.

See you next year mate... But Hey... Call me up for the co-op ones

Garry's Mod.

Unfortunately, you won't be able to 100% FEAR3 since half of the achievements require co-op and multiplayer game sessions, and very few people bought the game, and for those who have, nobody plays it anyway, and even less online. Local co-op is not available in the PC version. There's apparently no dedicated servers either.

If you want some (insane) challenge, I'd recommend trying to get these achievements:

• Super Meat Boy's The Golden Gift! (Complete all levels in "The Kids Xmas" chapter in super meat world IN ONE PLAY SESSION.) or Golden God (100% the game)

• The Binding of Isaac's Golden God! (100% the game)

• Braid's Speed Run (Complete a full speed run, beating the challenge time.)

• On The Rain-Slick Precipice of Darkness, Episode One's Silent, But Deadly (Fight, and destroy the final Boss without using any healing items)

• Secret of the Magic Crystal's End Game (By the power of the Magic Crystals I was able to bring this Story to a Happy Ending!)

And yes, definitely, go play Psychonauts!