Here are the official switches for Windows Essentials 2012 offline installer Application ID's are in square brackets.

Windows Essentials 2012 includes the following applications:
- Microsoft Family Safety [FamilySafety]
- SkyDrive for Windows [WLSync]
- Windows Live Mail [Mail]
- Windows Live Messenger [Messenger]
- Windows Live Writer [Writer]
- Windows Movie Maker & Photo Gallery [MovieMaker]

Command Line Arguments:
/silent -- don't bug me, just install everything **
/AppSelect:[app you wish to install],[other app to install],[etc]
/noceip -- don't participate in the customer experience program **
/nohomepage -- don't reset the homepage **
/nolaunch -- don't immediately launch components after install **
/nomu -- no msupdate
/nosearch -- don't mess with the search settings **
/notoolbarceip -- toolbar ceip **

Syntax example:

 WLSetup-all.exe /silent /NoToolbarCEIP /NoCEIP /NoHomepage /NoLaunch /NoSearch /AppSelect:WLSync,Mail,Writer,MovieMaker

All credit to this post http://forums.mydigitallife.info/threads/36086-Windows-Essentials-2012-Unattend-Install