To fix autoplay for DVDs under Windows 2000 you need to change this registry entry:
HKEY_CLASSES_ROOT\DVD\shell\play\command
From:
(Default) REG_EXPAND_SZ = c:\winnt\system32\dvdplay.exe /play %1
To:
(Default) REG_EXPAND_SZ = c:\program files\videolan\vlc\vlc.exe %1
Works fine for me!