I highly recommend the Panasonic SA-XR55 or SA-XR57 receiver. The XR57 is better, but a little more expensive, and has HDMI support. Both are all digital receivers that can put out a full 100w into all 7 channels with excellent THD and frequency response. The bottom line is that it's the absolute best sounding reciever for the money. Check out the like, 26 page thread on AVSForum about it if you don't believe me. It stacks up to multi-thousand dollar recievers from audiophiles companies like Rotel. Why? Because Panasonic is a huge electronics house with GOOD engineers that know what they are doing. Also because audiophile products are way overpriced.
Anyway. There are a ton of great brands for speakers. At any given price point there's usually half a dozen choices, and they'll all be good. For your price point, Athena offers the best bang for buck. There are others (Paradigm, Axiom, Energy, among many) but you'd have to stretch over $1,000 I think.
From Athena...
Front and rear speakers:
AS-B1.2 bookshelves
Center channel:
AS-C1.2
Subwoofer:
AS-P4000 or the
AS-P6000 if you have a large listening room or are just crazy about bass.
Or, to save a bit of money and get things in a smaller package, the
Athena Micra 6 system. It'll be more expensive than stuff from say, Logitech, but will sound way better. This is about the only HTIB (home theater in a box) speaker set I've been able to find that doesn't suck. I've been trying to get my dad to buy it for himself for sometime but he's too cheap.
Two very popular subwoofers are the Dayton
10" and
12" from PartsExpress. Dayton is their in-house brand. These two subs are pretty popular for providing deep, clean bass without having to break your wallet.
Also, if you look at Athena's site, you may be wondering if you can buy the AS-B2.2 bookshelves as an upgrade. Don't bother. The only difference is that the woofer is an inch bigger, which provides more bass, but you don't need that since you have a subwoofer. They are otherwise identical.
Another nice thing about Athena is that you can buy them from MANY places online and from local retails. Even Best Buy carries them. You'll have to push your way past all the Bose and Sony garbage out in the front, but they are supposed to carry them. At my local one all they had was a center channel in a beat up box in the way back. :/
Here's a breakdown for you:
Athena AS-B1.2s, 2x - $240
AS-C1.2, 1x
AS-P4000, 1x - $150
Panasonic SA-XR57, $300
Total - $830
Shipping's going to cost you a little, but hopefully you can buy the Athena stuff from a local retailer (they should have a retailer finding function on their site). The AS-B1.2s are supposed to retail at Best Buy for $100, so you could definitely shave off some cost there. I think AudioAdvisor used to sell them for $100, I'm not sure what's up with the price increase.
Or if you just get the Micra 6 and the XR57, the total would be $600. You can also save $70 by downgrading the receiver to an
XR55. Or you can buy a much cheaper analog receiver from say, Onkyo. They're a good choice, just not as good of a choice. The Panny receivers have more benefits than sound, too. They just have really nice interfaces with lots of options and great IO for lots of devices. The XR57 especially so.
Personally, I would go with the full Athena setup. You can save some money by buying locally and going with a Dayton sub instead of an Athena one. You could also buy a cheaper receiver, but that will gimp you in the future if you ever decide to upgrade your speakers. The XR-57 is a hell of a device that can be used effectively for MUCH higher end speakers. If you must keep under $700, and you can't get the price of a full Athena set down by buying locally, go with the Micra set. It's cheap but still delivers some nice room-filling sound. It's a steal, really. The full Athena set will get you a much bigger, fuller, room-filling sound, however.
Whatever you do, don't buy some cheap HTIB setup from a retail store. Pretty much all of them suck. I also wouldn't recommend buying Logitech or Klipsch PC speakers. Even the most high end PC speakers don't hold a candle to a decent HT setup like I've outlined above. They're targetted towards gamers who love big bass, and thus are engineered for that and nothing else. And hell, the bass isn't even that good! It just booms and that's it.
You said you didn't need audiophile quality, but what I've outlined IS audiophile quality but still within your budget.
Bassoon, n. A brazen instrument into which a fool blows out his brains.