MEKKKK ALARM ALARM !!!!

WTF do you have in the /root folder? That's the "home" folder for the root user, and is not under /home but part of the rootfs.

Since you should not be logged as root normally I don't think it makes sense to store root's "private" stuff in /root. Just put your files somewhere else.

Recommendation:
become root, cd /root, and then try to (re)move whatever bigger files are clearly not necessary. If in doubt, you can run "du -h" from /root and post the output here (I assume you don't store your p0rn in /root).