Credit to EOU Findub and Dillon for Starting and Keeping up with this Topic! A Big Thank even to MightyMango that allowed me to help with this thread.
This list will cover every game that has unachievable/glitched achievements due of bad coding, server closure, delisting from the Marketplace and other special circumstances!
Do not suggest achievements that
-Take a ridiculous amount of time to achieve (i.e. Gears of War 2 "Veteran Gear")
-Require an extreme amount of skill to obtain (i.e. Guitar Hero and Rock Band games)
-Require the game to be played on a certain date (i.e. Brothers in Arms: HH "Remember September '44"
Achievements which are glitched but supposedly have patches SHOULD be included on this list, and will be noted as such.
This section of the thread will just cover achievement that CAN'T BE ACHIEVED! If an achievement is not impossible for EVERYONE, it may be glitchy, but it is not completely broken!
If any are missing or need to be removed, please post them here, note that for adding new games/achievements, it may need more people to confirm its unachievability.
Delisted Games from the Marketplace
-1 vs 100 (200G not obtainable anymore)
-Are You Smarter than a 5th Grade? (200G)
-Battlestar Galactica (200G)
-Chessmaster Live (200G)
-Coffeetime Crosswords (200G)
-Cyberball 2072 (200G)
-Dash of Destruction (200G)
-Diner Dash (200G)
-Dream Chronicles (200G)
-Double D Dodgeball (200G)
-Double Dragon (200G)
-Golden Axe (200G)
-Live Draft Tracker (200G)
-Live Score Tracker (45G)
-Lost Cities (200G)
-Lucha Fury (200G)
-Marble Blast Ultra (250G) (DLC taken off also)
-NBA 2K10 Draft Combine (200G)
-NBA Unrivaled (200G)
-Pinball FX (250G) (Can be purchased under Pinball FX2)
-Robotron 2084 (200G)
-Rootbeer Tapper (200G)
-Speedball 2 (200G)
-Smash TV (150G)
-Street of Rage 2 (200G)
-Ultimate Mortal Kombat 3 (200G)
-Yu-Gi-Oh! 5D's Decade Duel (200G)
-FIFA Street 3 > Arena Pack (250G)
-Full House Poker (50, achievements not obtainable anymore)
-Madden NFL 10 > AFL Legacy Pack (150G) (30G not obtainable for server closure)
-Marvel Ultimate Alliance 1 (250)* **
-Marvel Ultimate Alliance 2 (250)*
-Naruto: Rise Of A Ninja > Forests of Death Exams (250, but 200G unbotainable)
*Both Titles are still possible to complete if you already have the DLC*
**If you have the Gold Edition of MUA 1 it is also still possible**
***If you currently have these games on your HD, these achievements are all still achievable (except for Live Score Tracker/Smash TV). Also, if you have a friend who has these games, you can recover your gamertag and get these achievements as well.***
Delisted Windows Phone 7
^^ Temp Link Until I have a change to add to the list