Discrepancy in hard drive space; can I delete these files?
You can certainly delete the two temporary items in your list:


/System/Library/Caches/com.apple.coresymbolicationd/data/
/private/var/folders/zz/CFNetworkDownload_L4uNTH.tmp


Avoid deleting the folder structures but large files in these locations can be safely removed.

To be extra safe, restart your Mac first and then remove any files. The restart will ensure the files are not in use.