Howzit Bud,
1) Vici doesn't work on windows.
And don't worry about wich version of linux - I went down this route, much tears. Download Vicibox and install using Vicibox.
2) No - read the manuals, follow the how-to's. Vici isn't automagic and doesn't drive it self, but for the amount of effort you put in you get a LOT out.
3) When you log in to any Vicibox via ssh, this banner is displayed, yes its free:
Thank you for installing ViciBox Server v.4.0!
This software is available for free download at
http://www.vicibox.com. If you paid for this
software you have been ripped off. Please report
any fraud or abuses of this software to
abuse@vicidial.com.
Rudolf