IPv6 and IPv4 - how to shut off IPv6?

[Bruce Labitt]

As a result of the mythfest install, my computer was setup with FC6.  
I'm unfamiliar with gnome and most of the tools.  My connections to the 
outside world are excruciatingly slow.  (Connection to google takes 
minutes, other computers on the same network, seconds.)  I do know that 
my router does not like to pass through IPv6 info, so I am suspecting 
something like this.

Are there some tools I can use to determine what is actually happening?  
Firewall or traffic analysis?  If someone could show some sort usage it 
would be greatly appreciated.

TIA