Zone Alarm Pro - No version works, below 3.7 won't install, version 3-7 and above install but don't run as they should.
Norton Antivirus, OO Defrag 4.0 - Need Server Version to install on 2K3. OO Defrag 4.0 Server Edition has a bug which prevents you from accessing it's MMC Plug in more than one time per boot.
TweakUI Powertoy - Need version 2.0 to install on 2K3.
Old Hardware - a friend of mine has a really old (6-7 years) Realtec combo NIC (Coaxial/RJ45) which 2K3 won't install, it doesn't have the drivers (while XP and 2K have them).
3DMark 2003 - With XP i get 10 3DMarks more than with 2K3. For anything else it is faster than XP. I think even in game play it seams faster or at least as fast as XP, maybe it's just 3DMark.
Anything else worked more than fine. With this OS I watch DivX, play games, code software (VB and C++), encode divx, listen to audio...
2K3 comes with MediaPlayer 9.0 and DirectX 9.0. Installation is faster and easier than XP installation. I played many games and ran most of the well known benchmarks.
Logitech drivers dont work. thats another thing if you have a wireless keyboard and mouse
What does run:
• Office XP
• Leadtek TV2000XP DLX
• Paint Shop Pro 8
• Dreamweaver
• Creative Labs drivers and all the other junk for the Audigy 2
• Style XP