Hello , I am using Avast Free Version . I did a full system scan and well, i found 20 infected files : Threat Rootkit , Hidden File.
Its a very high threat , that cannot be repaired , moved into the chest or otherwise be done with anything . Since these are in a system folder , i havent tried deleteing them . Pleease Help !!! 
Have you just done a windows update as we have seen similar instances ?
What avast scan were you doing (e.g. any changes to the default settings) ?
Deletion is never a good first option, you have none left, although in this instance access was denied.
Yes, been doing a lot of Windows update. Just did a new installation of Windows, and now this. And i didnt delete them . I was trying to move them into the chest .
Also i was doing a Full System Scan
It is just that in your image the Action shown is Delete, that is why I made the comment.
If you have rebooted, I suspect that if you do a full system scan (default settings) again they probably won’t be detected/there. If you can do that and confirm ?