Running basic and updated Skype on Windows 7. Whenever I have Skype in my Toolbar or when I am using it, I am not able to access any other websites. I use IE, Firefox and Chrome, but problem occurs in all three.
I would check the Skype settings making sure what port is used.
It should be something like port 12794.
In your case most probably it is using the Port 80, that the browsers need to connect to the internet.