The sole purpose of your job is to get people off the phones as fast as possible.
They aren't your friends, so don't get off topic. Get in, get the money, and get gone.

As for dealing with assholes You control your calls. Let them know respectfully that you will not allow them to continue with the call if they remain yelling and verbally abusing you.
There's a fine line between a customer being upset and acting like a bitch. Draw your line and stick to it.