1. I don't know about your specific BDP, but you should not be seeing MULTI CH IN if you set it to BITSTREAM the audio soundtracks. The fact that you ARE seeing MULTI CH IN means that your players is decoding the audio first, and sending it to the receiver as PCM.
Not that this is a problem, per se, but since you've got a receiver that decodes everything, you may as well see those lights come on!
2. Sounds right, just make sure the input mode is set to "auto" and it will automatically prioritize the audio inputs, HDMI having first priority.
On a side note, for Zone 2 audio it would probably be easier to use analog cables, not optical. For one, you aren't hogging the digital inputs.... second, while the receiver can send digital audio to Zone 2, it can ONLY do it with 2-channel PCM. It won't "downsample" a 5.1 soundtrack to 2-channel output for Zone 2, so you may run into issues with your current setup.