Is Home Sharing and Internet Speed have any connection

I live in an area with extremely poor internet speed and cannot stream my movies from iTunes Cloud. I reasoned that I would download all my movies and then home share them from my iMac to my Apple TV's. However, when I try the movies take forever to load (on the ones that do load) and play choppy.

I have a wireless network set up with a Airport Extreme (5th Generation) and extended with an Airport Express (2nd Generation) and using a 2011 iMac as my media server.

Any suggestions would be appreciated.

Thanks,

Larry