With Adobe PDF Reader you can print multiple documents by selecting them in Windows Explorer > Right mouse click > Print.
With version 10.0 we noticed problem –  after first document is printer empty Adobe Reader X window opens. Only after it’s manually closed second document is printer and so on.

This seems to be caused by newly introduced Adobe Reader “Protected Mode”
Open Adobe Reader X > Edit > Preferences > General – Uncheck “Enable Protected Mode at startup”
Caution: Protected mode is a new security feature in Adobe Reader X and by disabling it you potentially increase security risks.

Adobe Reader X (10.0.1)
Windows XP