I can do that but I’m trying to free up memory.
Yes, the app I mentioned Towelroot will root the phone. I’m trying to see if anyone else has tried it.
Pull down at the top of the screen, press the gear, press ‘general’ and press ‘storage’ - it takes a few minutes for it to calculate what the space is being used for. Once you've jotted down the system, used, cached and misc numbers, press ‘used space’ and again within a minute or two it will calculate space used.
When you press on ‘applications’ it will take you to the application manager, and should show you what is taking up so much space.
Try jotting down the numbers for the different sections - if you've got Amazon video installed, I've found that it loves to download in the background videos you might want to watch offline. My biggest space hogs are Google Play music, as I always have a few hundred songs for listening to offline.