I'm not sure exactly, but from what I've gathered, GTalk is part of all Google stuff. I disabled the app, and I got so many errors. Are you thinking it's Google Talk? Because that's the Talk app, without the "G". If anything makes something stop just add it to the ignore. I have dozens of apps in Ignore now because once it's killed, I don't get the notifications I wanted previously. Task Killer is nice to have for those apps that you don't use often like a game or something. Just make sure you check them.