I think the Blockbuster program you have is like a red box or Netflix type program. It came with my Android, and I haven't used it but I think there are Blockbuster machines that allow you to rent movies.
Since the video rental service is becoming obsolete, the company is now turning to more modern ways of renting movies. I wouldn't put too much faith in the application or its ability to provide movies as I think there is a fee associated with the app.
My recommendation is enjoying your DTV or simply getting Netflix as it is a superior service in my humble opinion.
