Damaged files on external USB hard drive

I have recently had a problem where certain movies have a deck of cards like icon next to them when browsing my movies,

and these movies will either not play at all when selected, the wheel will constanntly spin when selected, or when finally playing are choppy and seem corrupted.

I have tried to rescynchronize these movies on the apple TV from my home computer, but the problem persists. Has anywone else seen this?

What kind of files are these, and which menu are they being played through?

The problem seems to be with iTunes purchase movies.I am using an external hard drive, WD 1Tbyte on the silver apple TV. My iTunes store movies and TV purchases are on there. It is the movies that all of the suddent have an issue. The Apple TV shows  the movies, but some of them have a strange icon to the right, like a greyed out deck of cards or files, these movies are now either not playing when selected, or are corrupted when the finally do play after the spinning wheel keeps going with a dark screen, but if i press play they will play with a lot of jitter as if the file is bad.

I connected the disk directly to my mac and did a disk utlity on it, nothing was wrong. I also synch the disc to a mac and the files on the mac (of these sames movies that have problems on AtV) play fine on the mac.