I just ran the Disk Cleanup, but that didn't clear the folder in question. It is just in the temp folder and is, according to the modified date, over a month old, so I figure it probably is ok to just delete it. The folders inside it seem to be some temp backup that windows made, as they are Program Files, ProgramData, Users, Windows, etc...
Not sure what this folder was for, but yeah, probably ok to clear it out so it stops interfering with Avast.