The site says that everything is compatible but I would like to know if everything truly is compatible such as will the motherboard wil fit so on and so forth and what power supply should I get I honestly dont trust the web site and is there room for improvement such as lowering the price without risking performance or maintaining the price and better performance.
Only thing is you picked a 32 bit OS. You need 64 bit to use all 8GB of RAM. I also have a rat 7. I like it, but they are really picky about the surface. I got a Razer Scarab and that works amazing compared to my old cloth mousepad. You might want to add a hyper 212+ or evo for overclocking. I would pick a microsoft sidewinder over that keyboard, but that is really just personal choice.
The processor you've picked is designed for overclocking. the phenom 2'sr un somehwat hot to begin with, and the AMD stock coolers are barely adequate for the processors at stock speeds. Once you start increasing the voltage for overclocking, the stock cooler won't cut it. NTM the stock AMD cooler fan is loud.
I'm getting the idea you don't plan on overclocking, which is why I suggested you look at the builds in my sig.