Home network downloaded movie streaming ..... flawless playback media player roku nas apple tv wd tv live boxe?

Ok. Heres my issue. I have alot of downloaded movies on a external hard drive. Currently I download movies on my computer, transfer them to my hard drive, then plug the hard drive into my wd tv media player and watch it on my tv. Im about to upgrade my tvs to ones with apps/wifi and buy the new WD Tv live player. Im looking for a easier way to stream movies to multiple tvs in the house. So here are my ideas(please give me any info on how to stream videos without lag):

1. Use my computer to share videos to my new wd tv live player. However I need an external hard drive in order to get the amount of storage i need for my movie collection. (about 1tb and growing) Will adding the external hard drive to my computers shared network slow down the streaming from the computer?

2. Use a hub like the Pogoplug Series 4 or the Akitio MyCloud Mini. I heard streaming videos from these two cloud services isnt lag or jitter free when watching on tvs though.

3. Buy a media player and external hard drive for each tv and watch like that. Honestly I hate this option because I know there has to be an easier way.

4. Buy a cloud service from Google or Microsoft and stream videos from there. (heard there is lag)

Please help. I just want to stream my large movie/tv collection in the easiest way to multiple tvs.

PS I found the Buffalo Technology LinkStation Pro Duo and alot of reviews say the streaming is very nice.