These will be unique to each server you choose; generally it'll be port 6667 (the standard irc port), the server is up to you, the default is the one I operate. You can find a whole list of them over at SearchIRC. As for channel, that will be the channel you establish for your site on the IRC server. (these questions are more suited for the thread on the pJIRC addon page at UBBDev)

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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