Windows Media Player 10
Download: Windows Media Player 10 for Windows XP
Copy mp10setup.exe to \$OEM$\$1\install\WMP10\

Add these lines to your batch file:
ECHO. ECHO Installing Windows Media Player 10 ECHO Please wait... start /wait %systemdrive%\install\WMP10\MP10Setup.exe /q:A /c:"setup_wm.exe /Q /R:N /DisallowSystemRestore"
RunOnceEx Example:
REG ADD %KEY%\030 /VE /D "Windows Media Player 10" /f REG ADD %KEY%\030 /V 1 /D "%systemdrive%\install\WMP10\MP10Setup.exe /q:A /c:\"setup_wm.exe /Q /R:N /DisallowSystemRestore\"" /f
SVCPack.inf Example:
Refer to this page for info if this is the only hotfix you are integrateing into your unattended setup
or if you need more info about the SVCPack.inf method.
1. Place a copy the MP10Setup.exe file in the I386\svcpack folder of you installation.
2. Add the following line above all other hot fixes in the [SetupHotfixesToRun] secton. (Make sure to get all the quotes!)
"MP10Setup.exe /q:A /c:""setup_wm.exe /Q /R:N /DisallowSystemRestore"""