Hi:
I'm not an expert, but here a few tips I feel I can offer.
www.audioholics.com - great site, they have "recommended" systems based on various price points. and alot of general information as well.
www.avsforums.com - a huge, and fiesty forum. If you find a brand you like of reciever and or speakers, you should be able to find a forum dedicated to talking about that equipment and it's pros, cons, and alternative.
www.monprice.com - buy connectors, wire at monoprice. They offer hdmi cables for a couple bucks that are equal or better to the overprices crap that monster sells.
www.bluejeanscable.com also good - probably slightly better, but more expensive than mono.
I don't know your price point, but I like axiomaudio.com for speakers. It's an internet direct company, but that have been around for 30 plus years, and have alot of credibility. I like to listen before I buy, but the prospect of getting $5K speakers for a third of the money convinced me to take the chance. (you can return stuff hassle free if you don't like it) - I kept it.
Common "pro" (yeah - take it for what it's worth) advice is to avoid cube type speakers and home theater in a box.
When you say "optical" audio- you really mean digital audio - Digital can be carried via a optical connection OR a rca looking connection - same quality -nothing magic about the optical. Although optical can minimize the chances of introducing a group loop, but that's getting ahead of things. Other poster's comment about going with HDMI for audio is true to the extent that some of the most advanced audio decoding schemes limit themselves to hdmi so it's not but given that hdmi is very prevelant, you should make sure your reciever can accomidate HDMI. however, outside of understanding the newer formates, hdmi won't give you better quality than digital audio.
my last bit of advice is to buy in pieces... I started with a reciever, DVD, and just two speakers, 2.0 basic sterio audio. Then I added a subwoofer for a 2.1 system.
I'm just now planning to add rear channel speakers for a 4.1 system. I'm building out a much nicer system than I could have if I spill my initial cash amoung five or seven speakers, woofers, etc all at once.
good luck - enjoy!