This is essentially just a copy of the information already at http://www.gaijingamers.com/viewtopic.php?t=1195, with a minimum of addition by me. It is rewritten here just so I can look at it easily while I am out shopping. If you find this information useful, you should really join Gaijin Gamers and support the community.

Ace Combat 6
Army of Two - menus and text in Japanese, voices in English. JP version can only play online with Japan and Korea
Assassin's Creed - main menu is in English but everything else is Japanese.
Banjo-Kazooie: Nuts & Bolts
Battle Field 2: Modern Combat (English voice acting, text in Japanese)
Beautiful Katamari
Biohazard 5
Bioshock. Voices and menus are in English but item descriptions and other in-game text is a mainly Japanese with limited English
Blue Dragon
Burnout Revenge (menus and popup text in Japanese, but voices and in game text in English)
Burnout Paradise
Burnout Paradise: Ultimate Box
Call of Duty 2
Call of Duty 3 (All English voice acting, mostly English menus)
Call of Duty 4 *Japanese text, voices and cut scenes in English
Chromehounds
Clannad
Condemned
Culdcept Saga
Dark Sector
Dead or Alive 4
Dead or Alive Extreme 2
Dead Rising
Devil May Cry 4
Dragon Ball Z: Burst Limit
Dynasty Warriors 4 Empires
Dynasty Warriors 4 Special
Dynasty Warriors 5
Dynasty Warriors 5 Empires
Dynasty Warriors 6 // 真・三国無双5
Dynasty Warriors Gundam International // ガンダム無双インターナショナル　 - Voices in English, everything else in Japanese
Earth Defense Force X
Enchant Arms
Everyparty
Fable (Xbox Live Original)
Far Cry 2
Fifa 06 Road to FIFA World Cup
Fifa World Cup 2006
Fight Night Round 3
Final Fantasy XI
Full Auto
Fuzion Frenzy 2
Gears of War
Ghost Recon Advanced Warfighter
Ghost Recon Advanced Warfighter 2
Guitar Hero III
Guitar Hero III: Aerosmith Edition
Halo
Halo 2
Halo 3. Menu and subtitles are available in English but in-game voices are in Japanese
Idol Master
Idolmaster: Live for You!
Infinite Undiscovery
Jade Empire
John Woo Presents: Stranglehold
Kameo
Kengo Zero
King Kong
Kingdom Under Fire: Circle of Doom
Left 4 Dead
Lost Planet
Lost Odyssey *Japanese Menus, English voice
Love Football
Madden NFL 07
Madden 09
Major League Baseball 2k6
Moto GP 06
Musou Orochi
Musou Orochi 2
NBA Live 06
NBA Live 07
Need for Speed: Carbon
Need for Speed: Most Wanted
Need for Speed: Undercover
Ninety Nine Nights
Ninja Gaiden 2
Onee Chanbara VorteX
Over G
Operation Darkness all game menus and text are in English only the voice acting is in Japanese
Perfect Dark Zero
PGR 3
PGR 4 (Project Gotham Racing)
Phantasy Star Universe
Prey
Prince of Persia
Pro Baseball Spirits 3
Project Sylpheed
Raiden 4
Rainbow 6: Vegas
Ridge Racer 6
Riot Act
Rockstar Table Tennis
Rumble Roses XX
Saint Row
Samurai Warriors 2
Senko no Rondo Rev X
Shutokou Battle X
Sonic the Hedgehog
Spectral Force 3
Street Fighter 4
Soulcalibur IV
Super Robot Taisen XO
Tales of Vesperia
Tenchu Senran
Tetris: the Grand Master Ace
The Conbini 200X
The Orange Box
The Godfather
The Outfit
Tiger Woods PGA Tour 06
Tomb Raider Legend
Tomb Raider Anniversary
Top Spin 2
Touryumon (Mahjong)
Trusty Bell
Vampire Rain
Virtua Fighter 5
Viva! Pinata
Viva Pinata Party Animals
Viva Pinata 2: Trouble in Paradise
World Soccer Winning Eleven X
Winning Eleven 2008
Wrestle Kingdom
WWE2007 Smackdown vs. Raw
Xmen the Official Game
Zega Pain NOT
Zega Pain XOR
Ziria: East of Eden
Zoids Infinity EX Neo

KEY:
BLUE Japanese version has full English support
GREEN Japanese version has partial English support
RED Japanese version does not support English
BOLD Exclusive to Japan at time of posting

Games listed above that are neither colored, nor in bold, are released in Japan, but we don't currently know the status of the language support.

We are very grateful to Warrack/The Rani who originally maintained the compatibility list. This list represents a combination of his work, and the submissions of gaijingamers.com members.