pop ups on computer

I hope someone can help me.I keep getting stupid pop ups. Most of them have Yahoo on top and are some sort of games. They come up on Firefox and Chrome. I did a search and it says to to make sure in your tools that the pop up blocker is on and it is but still getting these F^&^%%* pop ups and they are driving me nuts

thanks

Al

http://feeds.feedburner.com/~ff/lumberjocks-topics?d=yIl2AUoC8zA