Jewish? ancestry.com says so...jewgen cant find it though..where do i go?

I have been trying to do some research on my family, and on ancestry.com in the search page, bottom right, there is a jewish family records history selection. Well i found some of my family and now im jut excited to figure out if this is actually correct. I however cannot find ANY other information with family or on these websites...so does ANYONE know if ancestry.com is just plain correct? Would a rabbi trust it? And are there any websites that i can keep trying?