Create and invoke the following registry file to disable the annoying welcome screen in Acrobat X Pro on Windows:
Disable_Acrobat_X_Pro_Welcome_Screen.reg contents:
REGEDIT4
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Adobe\Adobe Acrobat\10.0\FeatureLockDown\cWelcomeScreen]
"bShowWelcomeScreen"=dword:00000000