A wireless extender will help with your connection on that floor. Place the extender in an area with a full signal strength for the best results. The drawback with using the extender is you are limited to the best areas to set it up. Losing a bar or two in signal strength from the source will dramatically reduce the speed. On the upside a wireless extender is cheap.
NETGEAR Wi-Fi Range Extender EX6120
A better option is to use ethernet over the power lines. It's a bit expensive but can be set up anywhere there is power. I use this option to hardwire my desktop and get a strong signal upstairs.
NETGEAR Powerline 500 + N300 WiFi and 1 Port Starter Kit (XWNB5201)
Honestly don't use MoCA (just don't), your best option is running an Ethernet cable to another wifi router or access point downstairs (best/most reliable solution, yet maybe not the most pretty), Or like others have suggested using a power line adapter to wifi access point like this one (http://www.amazon.com/NETGEAR-Powerline-N300-Starter-XWNB5201/dp/B009WG6K66/ref=sr_1_1?ie=UTF8&qid=1440140023&sr=8-1&keywords=netgear+powerline+wifi) Or Use a wifi repeater (one that picks up and re-broadcasts the wifi) Like this netgear (http://www.amazon.com/NETGEAR-AC1200-Power-700mW-Extender/dp/B00HQ883QW/ref=sr_1_2?ie=UTF8&qid=1440140116&sr=8-2&keywords=netgear+1200ac) That Netgear 1200AC is incredibly powerful and will be a great solution as well. Remember, with technology (ESPECIALLY WIFI) you get what you pay for! I do third party work for CC, these WG wifi are garbage! Spend the extra money now, and save yourself from a headache later!