Here's my list of retail copies. I'm looking to collect a bunch more. I'm doing this from memory based on a list of the USA released DC games so I might be overlooking a few US ones. (Most of my collection is a couple hundred miles away atm)
PAL:
Shenmue II (I bought it brand new in the shrinkwrap and once opened, one of the notoriously fragile PAL plastic disc cases was already broken beyond repair

)
JPN:
Frame Gride
Dead or Alive 2 LE
Capcom vs SNK 2
REZ
Hong Kong:
Xing Hong VCD Player with remote
USA:
Airforce Delta
Alien Front Online
Armada
Bang! Gunship Elite
Blue Stinger (broken copy that doesn't boot)
ChuChu Rocket
E.G.G. (Elemental Gimmick Gear)
Evolution 2: Far Off Promise
Fatal Fury: Mark of the Wolves
Gauntlet Legends
Grandia II
Jet Grind Radio
King of Fighters Evolution, The
Maken X
Marvel vs. Capcom
Marvel vs. Capcom 2
MDK 2
Metropolis Street Racer
Mortal Kombat Gold
NFL 2K1 (came with my used Sports edition DC)
Outtrigger
Phantasy Star Online
Power Stone 2
Project Justice
Record of Lodoss War
Sega Smash Pack Volume 1
Shenmue
Sonic Adventure
Sonic Adventure 2
Sonic Shuffle
Soul Calibur
Super Magnetic Neo
Tech Romancer
Test Drive Le Mans
Tokyo Xtreme Racer 2
Unreal Tournament
Virtual On: Oratorio Tangram
Worms World Party
Last Blade 2
Also multiple versions of the web browsers and copies of the DC generator demo disc.
Want list: Sturmwind, Gunlord, Vanishing Point, F355 Challenge, Silver, Aerowings 2, CvSNK 1, Headhunter, Rippin Riders, Daytona USA, Test Drive V Rally, Jo Jo's Bizarre Adventure, Sword of the Berserk, 18 Wheeler, Sega GT, Pod Speedzone, Gigawing 1, Gigawing 2, Mars Matrix, Skies of Arcadia, GGX, Cosmic Smash, Ikaruga, Chaos Field, Karous.
Money is tight atm, and even though a bunch of the titles on my want list are common and relatively cheap, I'm waiting for the right game lot on ebay that will have maybe 4 or more of the common USA titles for a decent price.