Good luck with your build man, looks like we are working on similar setups, but I am going for a rackmount setup, that won't be directly connected to a TV.
Here is my thread...
Has anyone built a (rackmount) server. Thoughts?
Also, for playing media, check this app out!!
Plex - A Complete Media Solution
The server software is free, the PC clients are free. I got the android client for my Galaxy Note which was $5, but that's not too bad. Once it is all set up, I should be able to stream music or video to my phone from the server at my house.
As for what you said about not being able to connect the TV via ethernet, if you are in the market for a new TV, get a SMART TV with an Ethernet Jack. My Sont is connected to the net right now. The newer Samsung TV's have an app for plex media player which I believe is free, and that might be my next TV purchase.