The question covers two things. Ancestry is both a genealogy database service and a genealogy program in the cloud. It is actually a pretty good database service, and the best single repository out there, but you have to get back to WW II for veterans or 1930 for people in the US to start getting good info. If you have younger grandparents you might ask to find out about their parents and search for them. This will be an issue whatever source you use, as 1930 is the most recent Census released.
As a cloud-based genealogy program Ancestry is just average, and not something you would normally use unless you want the service behind it.