I was using the built in video app on the iPad, not a new app that I down loaded. Also, running iOS 5.0 No update to 5.1
Edited to Add: I deleted the two videos and downloaded again. They now work fine. Apple is just a tiny bit richer.
A week ago I purchased two music videos. They were playing fine. Now today they won't play and I get a pop up which says The URL can not be found on this server. I tried rebooting the iPad2 and resynching to my laptop. No help. Both videos play fine in iTunes on my laptop. Any ideas?