I also forgot to note the operating system. I would highly recommend XBMCbuntu. I often use it. It can also do 4K video playback fairly decently. I was able to playback 4K video on the h-264 codec on my Dell latitude D530, which has a Core 2 Duo T7250. The CPU on this motherboard should be able to do the same.
A build similar to this should work well for say, my 80 year old grandmother for web browsing, no? I would probably throw XP on it for her. She is still using something like a 700mhz cpu with 512mb of ram.