@echo off
taskkill /IM itunes.exe
echo Waiting for termination to complete...
PING 1.1.1.1 -n 1 -w 5000 >NUL
echo Starting iTunes...
start "" "C:\Program Files (x86)\iTunes\iTunes.exe"

I needed to do this because sometimes iTunes and my AppleTV will forget that they know how to talk to each other. Restarting iTunes always fixes the problem, so I wanted to make a button on my remote that would accomplish this. I made the above batch file and assigned it a keyboard shortcut, which I then taught my remote how to send. Problem solved!

Obviously this process would be useful for restarting things other than iTunes.

My use of taskkill is a soft shutdown. It sends a request to the process to close itself as if you had hit the X. If you need to force a task to shutdown, add /F at the end for "force."

The PING command is a bit of a hack to insert a 5 second pause between the previous line and the next to give iTunes enough time to shut down gracefully.

Finally, the use of a start command to launch iTunes ensures that this is launched asynchronously from the batch file's process. Without using "start" the command window that runs the batch file would actually sit open until iTunes was next closed.