Good CPU and MOBO?

Yup, that's a decent motherboard if you're only interested in using the onboard graphics or a single GPU. The CPU is good for the price, if you are interested in overclocking it, but for just $4 more you can get the 955BE which will work with newer AM3 only boards, and is .2GHz faster. If you have no interest in overclocking then you may as well just go with the 945 as it is the same speed as the 940 but is a little cheaper at $150.99

http://www.newegg.com/Product/Product.aspx?Item=N82E16819103809
 
Unknown lists a pretty good board, but we don’t know what you need from the board. Also the chip you should be looking at is the 955 because it is only a few dollars more. This one has the c3 stepping hence it will run cooler and overclock higher: http://www.newegg.com/Product/Product.aspx?Item=N82E16819103808&cm_re=x4_955-_-19-103-808-_-Product

As for the memory g.skill is a good brand but I would wait until you have a board chosen. When you choose your board you can pick ram that is on your boards list of qualified ram.