Transfering Music, Videos, Pics to Thunderbolt

I had some issues also. I use vista (I know lame). When I connected the TB to the PC as a disk drive, it wouldn't show on my computer, and explorer would freeze. But when I changed the setting on the TB to Media Sync, then I was able to drag and drop.
 
Why do i have duplicate files? Camera Shots & All Photo's - Videos 7 All videos. Same content. Which can i delete?
I don't think the actual files are duplicated; they just show up in multiple categories but there should only be one copy of the physical file. Best way to confirm is to use Astro File Manager and look at the file directory.