It is hard to recommend updating cpus on a board that old. I do recommend getting a new cpu/motherboard/memory/gpu. Yeah, that's a lot of hardware and dough, but in end you will much happier playing games on a newer rig. If you do take that route, let us know a budget and we can help ya with that. We also need to know your screen resolution.
You can pick up a Phenom II X4 for less than $100. That is about as good as you can do on that board. If you are looking at something a little more substantial, then I recommend going with either the AMD FX 6300 or the I3 3220 and a $50 board and $40 for 8gb of ram. That'll run you around $220. You'll still need a better GPU, but the 240 should be okay for now.