Can I connect HDMI #1 and HDMI #2 and get the video from HDMI #1 BUT the audio from HDMI #2?
no, unfortunately. mixing of audio/video from two different HDMI sources is not possible (due to HDMI copyright restrictions).
your best bet (I am assuming you will use this to stream music from a PS3 or other media player while watching TV) is to connect the cable box straight to the TV for video, allowing you to use whatever audio source you want on the receiver.
Also, why does this receiver (like every other receiver) contain so many ancient outdated extinct ports like composite and component?
wait, what???? actually, it contains very few legacy connections!! There is only ONE component video input, two composite video inputs, and three analog audio inputs! You think that's a lot?
So many modern devices use HDMI and optical (toslink and coax) yet receivers put tons of composite and component ports but rarely any digital ports.
that is, like, the opposite of the truth. Industry wide, entry-level receivers have been moving more and more to almost all HDMI connections with very limited legacy connections. Compare the back panel of the AVR 591 to an entry-level receiver from 3-4 years ago. You have 4 HDMI inputs, plus two digital audio inputs and almost no legacy connections. That is SIX digital audio options and FIVE hi-def video options (4 HDMI + 1 component) versus only three analog audio inputs and three SD video inputs.
This receiver is designed for an all-HDMI setup basically. Your comments are strange, to say the least! Most people complain about the opposite (not having enough legacy connections).