You may need new ram depending on what model ram you have now, it should be 1.5v or less and for a dual channel mobo, you need your ram in pairs, so the triple channel kit you have may work, but it's not ideal, it'll only run in single channel mode, and if you only use 2 sticks, you'll only have 4GB.
You can find 2x4GB kits for less than $40. I see no reason to upgrade your power supply.
Unless you get a cloning software, you will need to buy a new copy of Windows. (I don't recommend cloning, you want a clean install for maximum performance IMO)
Besides GPU and SSD, I don't have any recommendations for your rig. Everything else seems pretty, especially your PSU. I can say you won't need to upgrade your PSU for any of the single GPU cards out on the market today.