That unit doesn't have a Wireless Internet Card, you'll still have to go out and buy one, the unit I scrapped together for you comes with one. (Unless installing a wireless card is too damn difficult for you...) I cannot support you buying one of those little USB ones, those are better suited towards laptops.
All the steel series is crap, in my opinion, but that's a personal thing.
Why do you need a VGA to HDMI cable when you stated before your current monitor has a VGA one...unless it really is HDMI, which is infact, not a big blue, but a smaller, slender black cable. According to the specs of the prebuilt that you're getting, it has slots for VGA, DVI and HDMI...?