I'm new to rooting my phone, but I was thinking of trying out the KDE tablet interface on my Nexus 7. I'm probably not going to keep using this, since I like the huge app ecosystem on Android, so is it possible to reinstall stock Android on my tablet?
Yes. One option would be to use the images distributed by Google at Factory Images for Nexus Devices. Download the appropriate package (the 4.2.1 Nexus 7 archive is what you'd presumably want) and then either flash the images manually or use the included
flash-all.sh script (if on Linux). Manually running the commands will be of the form:
fastboot flash <partition name> /path/to/image.img
So, as an example, you'd flash the system partition with:
fastboot flash system /path/to/system.img
You'll need to have the
fastboot utility configured for this, but it will work regardless of what OS or recovery system are installed on the N7 at the time as long as you don't modify the bootloader. You'll also need to use
fastboot oem unlock to unlock your bootloader if you haven't already, which will wipe your personal data.