Smooth like a console? Consoles, hardware wise, are utter crap now. They're still stuck back in 2005. You're Phenom II is hardly cutting edge, but even so its more powerful than anything you'll dig out of the inside of a console.
You don't NEED to overclock your CPU, but yes, it will help. And providing that you have a decent after market cooler fitted its also quite easy to do. Personally I would avoid messing with the graphics card though. CPU's are quite robust, you can push them quite hard and they generally don't fail that often. But graphics cards are comparatively fragile, especially when you start overclocking them, so just be careful.