|If nothing else is slow, the issue is likely yahoo and not your router.|
If everything else loads slowly, it could be the router, it could be your computer(s), or it could be your internet connection.
If your router were the issue, I'd expect everything to load slowly, not just one, or two, or three (etc) websites.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.