I'm having the same issue with mine. The touch screen will randomly stop working. Does seem to come back after a while though.

Same laptop, same issue with me.   Restarting laptop fixes it for a while.  Also if I wait a really long time (5+ minutes), the touch screen typically will work again.  I thought it was hung up doing automatic Windows updates, but I turned the automatic update feature off, and touch screen still often stops working.

I have submitted this problem a few months ago, other people have obviously the same issue, and no reaction from DELL ???

Happened to me again last weekend. Seems like the dell quickset app stopped functioning as the power management was all messed up while this occurred (no screen dimming, sleep).

I had the same problem and found touching the metal casing with my other hand had an effect

Here's a video I did showing what happened

http://www.youtube.com/watch?v=B3fWIEtOFfk

My screen very occasionally will stop working with touch.  On every occasion it has been running on the battery and playing a game (not always the same one).  Rebooting always fixes the problem, but what I haven't tried yet is plugging in the power and / or waiting several minutes to see if it comes back.  I'll post further if I get any more info.

Didn't work for me, I turned this feature off some weeks ago (and confirmed it is still off).  However, I still suspect a particular software game program.  I won't mention anything just yet.

I read elsewhere that if you turn the screen auto-rotate feature (button on left side back) the touch screen should no longer freeze.  This worked for my XPS 12..