Arcady's right. But to answer the second question, the TiVo indicates which shows are copy protected, when you're looking to copy them. (However I don't believe there's any easy way to check if a show was copy protected directly from the TiVo it was recorded on. You need to be looking from a device capable of transfering shows from it)
When looking at the Now Playing list from the remote device (another TiVo, the iPad App, TiVo Desktop) copy protected shows will have a 'no' symbol (red cicle with a slash through it) to the left of them.