Now you are settled down with your Windows 8/Windows RT Tablet, which you bought/got during holiday period. Now you realized the 32GB or 64GB system which you got has less than 10GB or 30GB of free space for you to play after many firmware and system updates. Don’t worry you could reclaim a good amount of free space. I reclaimed good amount of disk space my 64GB Surface RT and 32GB Dell Venue 8 Pro with disk clean up.
Also Windows keeps older version of Windows if you are upgrading from older Windows system in C:Windows.old. In order to free up this folder and any other updates such as firmware and other installation temporary files and recoup the storage space, just use the Disk Cleanup utility. Start typing Disk Cleanup on your Windows 8.1 start screen to open the utility. Once it is opened click on Free up disk space shortcut. Once it scans and gives the free space you could recoup, click on the Cleanup system files, and once it presents with additional options, enable the Previous Windows Installation(s) option in the list and execute. This may give additional space if the previous windows installation is not deleted already. In any case, you have the ability to free up some more space.
Hope this helps.