what is best wifi hotspot hardware/software?

Zyxel N4100 is a good choice.

As far as the hardware is concerned you can go with Linksys AP's as they are cheap and reliable since the hardware inside them is by Cisco systems... For the software part you don't need anything special.... Just configure the AP and connect the WiFi device you wish to the network and run the application you need. I would go with windows server software if needed, for better compatibility.

you can go with Linksys AP's as they are cheap and reliable since the hardware inside them is by Cisco systems...

Belkin acquired Linksys in 2013.  Aside from that, Cisco have never used their own hardware in Linksys products, hence the vast difference in price and features.

Maybe I should clarify the "by Cisco" part.....either way its a reliable solution.... Configured many of those and are still up and running

You mean older kit then.  Linksys hasn't been 'by Cisco' in over a year now'. :-)

I agree though - they are pretty reliable (Linksys by Cisco devices) and can be easily integrated into the Zyxel solution.  In fact, just plug them into the Zyxel router (obviously configure wireless settings) and it's done.

2600 is proper Cisco.  Probably overkill too.  1600 would be better suited.