The motherboard only supports DDR3 RAM, but the RAM you linked is DDR2. It's a good mobo, Asus and Gigabyte have the best boards I've ever worked with since DFI went under.
I recommend a set of G.SKILL Ripjaws.
http://www.newegg.com/Product/Produc...82E16820231276
http://www.newegg.com/Product/Produc...82E16820231277
http://www.newegg.com/Product/Produc...82E16820231303
The last one is the exact RAM I have in my system right now. I used to swear by Crucial Ballistix, but ever since a few sticks died on me, I've been using G.SKILL, and can vouch for the quality.
The GTS450 and the HD5770 both typically cost the exact same, and trade off performance depending on the games/benchmarks. They're both about equal to each other, and should take on any game out right now at max settings. Good price on it right now, so I might just pick one up myself to replace my HD4650. =D
The optical drive should be fine, but if you're worried about the quality, check out Lite-On. Their drives are fairly dependable.
http://www.newegg.com/Product/Produc...82E16827106334
This is the same drive I own on 3 systems. Never once had a problem with it.
The case should be fine, though you may want to invest in a couple fans for it. For the price of the fans, you could probably swap out to a case with the fans, as well as better cooling.
http://www.newegg.com/Product/Produc...82E16811196034
^ Same price as your current choice
http://www.newegg.com/Product/Produc...82E16811196035
http://www.newegg.com/Product/Produc...82E16811103021
I can't really comment on the hard drive, or power supply, as I've never done business with Samsung, and the only Cooler Master products I've ever used were their heatsinks, and cases, both of which are great.
If you haven't considered doing so, you would be much better off getting a heatsink, since the one AMD supplies is quite awful. They're just a solid block of aluminum with fins and a very small 5 or 6 cm fan attached on top. If I knew where my digital camera was, I'd snap a photo of it.
http://www.newegg.com/Product/Produc...82E16835103064
^ Sadly, the price went up since I got mine. Was $15 last November-December. It keeps my Phenom II X4 B50 running at around 40C at 3.6ghz while gaming.
EDIT: Found a pic of the stock heatsink.
http://www.goldfries.com/hardware-re...cessor-review/