Slow wireless network, cannot stream movies

Here is my setup

linksys 4200 router connected to internet

linksys  WES610N wired to wd tv live hub and tv (connects to router at 5 GHz)

linksys  AE2500 in my laptop

every thing is connected 

but cannot stream movies from laptop or from hub, only mp3 or small tv shows could be streamed

what am i doing wrong?

thanks.

Do you get the same problem with a wired connection?