You have pretty good hardware balance in your current machine. Each of your components are a pretty good match for each other, just not very powerful. I recommend a complete rebuild.
AMD Ryzen 7 (formerly Zen codenamed Summit Ridge, competes with Intel i7) is currently dethroning FX as the king of AMD. Let's wait for the release of Ryzen 5 (competes with i5) and Ryzen 3 (competes with i3) before we suggest a CPU from Intel that might be outdone at a cheaper price by a Ryzen chip.
As for the graphics card, what's your budget?
You don't have much knowledge of computers... Well do you have two hands and a brain? You do! Well then you can build a computer.
It's actually very simple. Advancements in the user friendliness of technology coupled by the adoption of modern standards means that building a computer is about as hard as working with LEGOs. Everything is literally designed to fit together without issue. There's even a website that will check prices across the web and check for compatibility for you.
http://www.pcpartpicker.com
It used to be complicated, but that's all changed now.
1) Your CPU comes with a heat-spreader on it. You don't have to worry about damaging the die just because you mounted the cooler incorrectly.
2) You can put your RAM into slots on the motherboard and it works! No electrical knowledge or soldering equipment necessary!
3) You can just plug your hard drives into power and SATA on the motherboard and it just works. No messing with jumpers or entering drive specs into BIOS required!
4) Finally, and this is a big one for me, power supplies have standard connectors. I hated the old days when I had to make power adapters just because connector standards weren't widely accepted by manufacturers yet.