noob questions

[bevisiscariot]

Okay, so I've got all this stuff (46" Sony Bravia TV, PS3, directTV box, old sony a/v receiver, fluance av-htb speakers, half-dozen blu-ray discs) and I'm a little overwhelmed. So many options - makes my head spin.
I know I can't get HD from the direct tv box because it only has composite hookups on the back, so right now I'm watching tv in sd. But I've got the ps3 hooked up to the tv via hdmi and the picture looks great with the blu-ray discs so I figure that's all good. Because the receiver is an older model, the best it offers is optical so I have that hooked up to the ps3 that way.
The speakers are all properly hooked up with decent cables and placed well and the receiver decodes dolby digital and dts. But . . . there are like a million settings on the tv, the ps3 and the receiver and I don't know if am getting all i can out of this stuff.
It's a good thing to have the black bars when watching blu-ray, right? I don't understand much about aspect ratios. My tv offers normal, full, zoom and wide zoom. Are their any dvds with aspect ratios that fill the screen without cropping or loss of picture quality? And what about the ps3s limited and full rgb options and the super-white option - what are the best? Finally, how should I set the upscaler on the ps3 for my reg dvds - normal, double?