Internet Speed

Unless you're having buffering issues (e.g. playback stops or takes a long time to start), no.

No. :) 

96k/24 bits = ~ 5 Mbps

A more important thing is if you are using Wifi use a phone or laptop app to ensure you are using a good channel with lots of signal and few competing neighbors.

No.
 

As @erik_squires  point out the requirement is really small and streamers cashe the input. I can struggle with my iPad changing pages and my streamer goes on playing without a hitch. 

Sound quality is primarily driven by the quality of your streamer.

I should have been more clear.  Phones and laptops have free Wifi analyzer apps which help you pick a good, unused channel.

5 GHz tends to be less congested and is faster so you should try it first.

@erik_squires 

+1 keeping in mind that the throughput of 5 ghz drops off with distance much faster than the 2.4 ghz channel. In general about twice as fast. In my house thirty to thirty five feet and the throughput of the 2.4 ghz channel eclipses the 5 ghz channel. I have extenders to assure maximum throughput everywhere.