I recently purchased an LG 47LM7600 and am looking for an audio setup to go along with it. It's going in a 15'x13' room. My current budget is about $400. I thought I'd go with a 2.1 setup to start and then upgrade later when I have the additional funds. Here's what I am currently thinking about purchasing:
I recently helped a friend hook up his HT gear. He's got a Pioneer VSX-522. It seems like a really nice receiver. MSRP at Newegg is the same as the Yamaha. (Unfortunately, while the Pioneer appears to be on sale, Newegg will only divulge the price once you get to the checkout.)
The Polk PSW-10 is a very modest sub. Don't expect too much from it and you won't be disappointed. The Dayton SUB-1000, with twice the power, is likely a better bet for $20 more.
Also I know your initial budget for speakers + sub is only $200ish, but you can also check out this Jamo set. Should slap those bookshelf speakers out of the water with even just the 2 towers initially and perhaps the center channel. I love mine for HT & the Xbox, it really does sound good for the price point. (to my credit I also have the Jamo 650 subwoofer that I bought a few months prior to the speaker set being on sale on Amazon, however compared to my P163s it has a much better sound stage in my video game tv setup)
Those Polk Monitor 30s are good budget speakers but are just that, budget speakers. I recently put together a 5.1 setup using Polk monitor 30's and the matching CS1 center for my father-in-law. He needed the entire setup to cost less than $300 so that is why I recommended them to him. You get alot of bang for your buck and to go beyond them, as far as sound quality goes, you will need to spend about $500 - $600 on speakers. So if you can't spend the extra money to step up to the next level, then the Polks will probably be your best bet for getting the best sound within that price range.
It seems that the monitor 30 series has been discontinued and replaced by these: http://www.newegg.com/Product/Product.aspx?Item=N82E16882290268
BTW, my father in law loves his Polks and is always talking about how it is like he in a real movie theater and he hears details that he never could before. He upgraded from a Kenwood all-in-one-box setup.