Need some audio system help!

[Avond]

Hello all!
I would just like to thank all of you in advance for any help you can provide.

I've been lurking around the forum for over a year now, but I rarely post. I just try to absorb all of the knowledge contained here However, I'm looking to upgrade my audio system from the HTIB I have now (Onkyo HTS590) and I would love to hear some expert advice. It used to suit my needs, but now I really want to take advantage of the lossless audio codecs. Additionally, for some reason, I can't hear any sound from my record player through that receiver and I cannot figure out why (if anyone has any ideas, please let me know!). As I understand it, I have two options. Get a new player that can decode the audio codecs and send them over optical cable to my reciver or get a new receiver as my player can bitstream (Sony BDP-S350). The only store that I have local is a Best Buy where I can demo speakers. Other than that, I'm out of luck.

I have a few questions:

1. If I buy a new receiver, can I use my old speakers for a bit while I save up money for some new speakers, or do I need to do this all at once? I was under the impression that I could NOT do this, but please let me know the correct answer.

2. I am thinking that it would be the nicest to get a new receiver and speakers and go that route rather than get a new player, just becuase the old speakers leave a little to be desired. I am, however, getting ready to move to a second-story apartment where the people below may be picky about the sound, which could be a problem. I would love to hear some opinions on which option might be best.

3. I was thinking about either the Denon AVT-590 as a first choice receiver with the Yamaha RX-465 as a backup choice. I'm still in grad school so money is very tight and I do not want to spend a ton of money on these, so my receiver budget would be somewhere around this range (no more than 350 I hope). Are there any opinions on either of these receivers or any others that would be good? I will be hooking up an OLD record player, my blu player and a Roku box. The HDMI out will go to a Samsung LCD TV.

4. I was thinking of maybe starting with a 2.1 setup (left, right and sub) and getting the rest of the components slowly. Will not having a center be a problem hearing dialogue in movies or playing music? Is it better to do a center and sub and build from there? Would love to hear some advice there.

5. I was thinking about the Polk TSi100 speakers for the left and right and a CS10 for the center. I listened to them in a store, and they sounded great to me. Any other suggestions?

6. I was thinking about a Klipsch SW350 sub. I absolutely LOVE this sub. The only issue I can think of is that it is a down firing sub and if I have neighbors downstairs, what is the probablility of them hating me? It seemed to have a "volume" control knob on the back, so maybe I could just turn it up for the things I really need to listen to some rocking tracks to (LOTR anyone? ) and turn it down at other times? Is that a reasonable option or should I not mess with it once it is calibrated?

Anyway, I"m sure I've forgotten some things, but I'm sure you'll remind me I would love to hear about some of your ideas and your opinions of my ideas. Any suggestions or great places to find a good deal are welcome! Thanks!