Actions: Forcing windows update and installation
A while ago I came across a VB script from Rob Dunn. I am using it successfully for years now. With PDQ Deploy you can "upload" and run the script on all machines connected to your WSUS server and this way force them to download and install all the patches/fixes from WSUS server and send a final report to your e-mail address.
The script (version 2.6a), including documentation, can be found at http://www.theitoolbox.com/?p=13
I highly recommend it.