Touch Screen

You can also try force reboot, by pressing the Power Key + the Volume Down Key for about 10 seconds. 

Running the phone in safemode can also help to check if a 3rd party application is causing the non response. If you are running on Jellybean you can run the device on safemode by Pressing the power key - wait for the pop up - then tap and hold "Power Off". You will be prompted to reboot to safe mode. Now if the device is working perfectly, try to uninstall the latest app you have installed until you have determine which app is causing the non response. 

You can also try clear cache partition, which will clear out clutter on your device. 

     Step 1: power your phone down

     Step 2: hold volume up, down, and power simultaneously

     Step 3: use the volume down to navigate to "recovery," use volume up to select

     Step 4: you will get a screen with a triangle with an exclamation point, next to an Android. Press volume up and down simultaneously

     Step 5: use the volume rocker to navigate to "wipe cache" and use the power button to select.

     Step 6: after it has finished, use the volume rocker to navigate to "reboot system now" and use the power button to select.

Last But not the least you can do hard reset, as the last resort.. or if it still the same.. repair as the final resolution...

Hope this helps!