HDDs. Virtually no difference in performance, the WDs are noisier and more expensive.
Mobo. Find a board you like, add your own WiFi, > http://www.newegg.co...2E16833555008
All good brands, Gigabyte, Asus, Asrock.
Case, Don't know that one..
I look for, washable filters, fans front, back and top, controllable if possible.
I am not all that keen on coloured fans, but some of the best case come that way, in that price range, this is the one I would buy,