Ok lets start with the motherboard not having the right socket for the CPU, your CPU has an AM3 socket, your MoBo FM1, this is a no go. now if your staying with the FX-4170 Zambezi you need a MoBo with a AM3 socket like this one. http://www.newegg.com/Product/Product.aspx?Item=N82E168... I've never used this brand but they have a good rating in NewEgg which is pretty reliable plus its less than the one you had picked out leaving room for other parts.
Now the Power supply, you might be able to EEEEKK by with the 500W you proposed but here more is better especially if you are going to upgrade this in the future, like SLI'd video card or overclocking your CPU. I would go with something more like this for a PSU http://www.newegg.com/Product/Product.aspx?Item=N82E168... it's Bronze rated and $69 right now after MIR.
Now for the aftermarket heat-sink, if you plan on overclocking I would recommend this http://www.newegg.com/Product/Product.aspx?Item=N82E168... if not the factory heat-sink would be fine, remember they designed the factory heat-sink to work with the processor within normal operating parameters.
Now DON"T buy that Toshiba HDD, OMG its J U N K ! 5400RPM? Useless! for the price range your shooting at go with this http://www.newegg.com/Product/Product.aspx?Item=N82E168... It is a 1Tb (same as both your drives combined) 7200RPM with a 32MB(Double your pic's) Cache. All this equates to faster access time all around with a single drive that costs less than your 2 combined.