How do I turn off Automatic Download?

Lately, iTunes on my computer has been evil with me. It's been acting up by crashing or not letting me download videos when it gives me the "error 50" message. Every time, I open up iTunes on my computer it starts downloading the Digital Copy of Rise of the Guardians and True Blood season 5. So how do I stop the iTunes program on my computer from automatically downloading? It is really annoying. My computer is a Lenovo laptop with Windows 8.