Q: my 3 gen will not play movies because I can't connect to iTunes, but I can purchase movies, watch trailers but can't play movies. Help?

Hello lori182,

Thanks for using the Apple Support Communities!

I understand that you can make purchases from your Apple TV, but is having trouble playing the content that you purchased and receive an error message. I see that you have already don’t a lot of great troubleshooting as well, but the issue continues. 

To continue troubleshooting this situation, I would recommend reading over and working through the suggested steps from the following article. 

Get help playing or streaming content on your Apple TV - Apple Support

Cheers!