ja ja
jaja means eggs in Polish and is pronounced
yaya. In the same way as you refer balls to some male's intimate organs, in Poland we call them eggs.
Grandfather is
dziadek and is pronounce like
jadeke sha veestray
WielkiPolak is right about translation but contrary to what he wrote, it makes a sense. It's quite childlish and yokel to say it. A person say it when he/she wants to manifest his/her disregard to things what someone just said or in a quarrel when someone called you a bad name you can say that in revenge. It's like saying
you talk cr*p but it's beyond any level of a class. Even educated people curse sometimes but this kind of phares shows that the person who uses it is a simpleton (or a kid) and that would cause a real embarrasment around. I'm sorry to tell you that.