Need Help With Playstation 3 Surround Sound System(im so confused :S

Ok, so I was watching the 20th anniversary demonstration that Kojima prductions did for MGS4...and was comparing it with the final version(im a comparison junkie XD )...and I noticed some thing was not the same. It was the sound!!! It sounded so much louder/crisper coming from the video demonstration compared to the one running on my PS3. The only thing I can think of it being is my sound system...which is just my HDTV . Ive got a 32" Sharp Aquos...and here are my two questions:

1. Can someone help me find a good surround sound system... I was looking at this one:

http://www.bestbuy.com/site/olspage.jsp?skuId=8822893&type=product&id=1207352155889

My budget is from 200-400 bucks

and my final question...

2. How much of a difference will this 5.1 surround sound system be from my HDTV?

http://www.bestbuy.com/site/olspage.jsp?_dyncharset=ISO-8859-1&id=pcat17071&type=page&st=HT-X50&sc=Global&cp=1&nrp=15&sp=&qp=&list=n&iht=y&usc=All+Categories&ks=960

I have this one by samsung. I think it is great for the money. It works great with movies music and games. It's 1000 watts and the sub is nice. Good all around for the money. I didn't see anything wrong with the one by Sony you were looking at though. It's 900 watts but it's $50 cheaper. I just wanted to let you know I love mine and I suggest it to you.

I have that system and love it.

edit: guess i should say that it's just the receiver and all speakers were purchased separately. In the end, about $1600 all together.

This is what I have and I love it. It's worth the price. It comes with HDMI inputs and 2 Optical Inputs. I know it's a tad bit over $400 but it's worth it trust me.

http://www.bestbuy.com/site/olspage.jsp?skuId=8457136&st=Sony+5.1&lp=8&type=product&cp=1&id=1184369166945