FYI: The statements of faith of both this group and the Reformed group are conservative. While this group is called Presbyterian, the largest Presbyterian bodies in both the US and Canada would not qualify by this group's official definition. The same is true of the Reformed group. The largest Reformed church in the US would not qualify. So these are by official definition actually *conservative* Presbyterian and *conservative* Reformed groups. There are no general-purpose Presbyterian or Reformed forums corresponding to the Lutheran, Methodist, and Restoration groups. Most members of the Presbyterian and Reformed forums are conservative, and are not receptive to the basic theological orientation of mainline churches such as the PC(USA), the United Church Canada, and the Presbyterian Church of Canada. There are certainly PC(USA) members who post here, but this might not be a comfortable place for UC Canada folks looking for a home.
The Methodist group includes in its definition pointers to a wide variety of Wesleyan groups, both conservative and mainline. I don't participate there, so I don't know the orientation of the membership. But if your congregation tends to Methodist theology, this might be appropriate for you.
While the United Church of Christ is a specific American denomination, so UC Canada doesn't fit according to the name, in fact it may be the closest of all the groups for UC Canada folks with a Presbyterian orientation. It is a mainline Reformed denomination, and thus is probably compatible theologically and in terms of church organization with the UC Canada. I doubt you'd have any problem with their faith statement, I'd guess the members would be friendly. It doesn't seem to be very active. (Yes, this contradicts my previous posting.)
The moderate and liberal forums should be OK for any mainline congregation. However moderate isn't very active, and liberal may be more liberal and more random than you want. The liberal forum is probably more active than most mentioned here, which might be an advantage in finding someone to talk with. Please check its groundrules (posted in a sticky message), since there are things you'd expect to be able to say in a liberal group that you can't say because of overall CF policies.
If there are several UC Canada people, you might want to pick one forum to use.