"So I guess when your ancestors came over here, they knew how to speak English right away?"

They knew how to speak it before they came over here. Father's side of the family from England in mid-1800's. Mother's side of the family, my great great (not sure how many greats) grandfather was Roger Williams, arrived in Boston in 1631. You mention American Indians. You probably aren't aware of what my great great (not sure how many greats) grandfather (my mom's dad received an invitation to every presidential inauguration due to our ancestry) did in this country during colonial times, but a pretty good description is here.
http://en.wikipedia.org/wiki/Roger_Williams_(theologian) For some reason, the entire link isn't clickable, so cut and paste it as shown or click on the (theologian) sub-link from that wiki link.