What's the most stable video conferencing freeware? For mom and brothers 24/7, without using key/mouse.?

I am trying to set up a box where my mom and I and brothers can talk over the net. I want to have the machine on at mom's 24/7 so she can always talk to us and we can always see what's going on at her house.

Any recommendations? My brother has ichat/isight from imac in the house but I haven't figured out how to set it open up all the video windows when it powers up. I am more familiar with windows boxes where I think I can set AIM or one of the messengers? or justin.tv to auto load and connect? I was having justin.tv drop every fwe hours tho.

Ideas? I am research linux solutions.

The end goal is just a very stable video conference box and experience for mom at home. Just leave the machine on. Nothing to press or click.
I am looking for a box where you don't have to log on , don't have to click. something that works without keyboard and mouse.