Genealogy / Krzesniak: Another Person Trying to find out about their Ancestry [4]

Hi, my Polish/American father passed away when my mother was pregnant with me. Due to some family issues my father's side of my family wasn't a part of my life growing up. I reconnected with my paternal grandfather right before he died so I never got to find out much about my Polish ancestry.

Now I have a son and since I'm a single parent I've passed the Polish name on to him and would like to discover more about the history of my family. I'm also planning a trip to Poland in August with my son and this will be my first time traveling outside the US.

Is Krzesniak a common Polish name? Will it be hard to trace the history? Any suggestions of where to start? Also, any suggestions of what I should see/do while visiting? Obviously I've read of the different attractions/touristy sites to see but anything else that comes to mind would be greatly appreciated.

Thanks!