Please supply more details.
Please confirm what you mean by system files into your Elements Organizer 12
a.. photos and videos imported into the Elements Organizer
b. something else?
How many of these files need to be deleted, and does this involve sorting out duplicates?
Is your goal to remove these files from just the Elements Organizer or from the Elements Organizer plus the computer hard drive save location?
(Just in case message, all you have in the Elements Organizer are copies of the originals that remain at the save location where they were when first imported
into the Elements Organizer).
Pending further information, the following may be of interest
Please consider, supply details, and then we can decide what next.