Depends on how big a family you are planning to have.If only one kid,a car will do,if two or more ,then you need a van.
Once you put a child car seat in the car,it takes a lot of space and if 2 more people sit next to the child,it becomes a little uncomfortable.If only you,your husband and child will be in the car,then any car will be spacious enough.
Most cars in the U.S. are very spacious inside...generally most Indians go for Toyota or Honda.These days I find a lot of Nissans too.
In my case,we got a Honda car first,then when my son started school,we went in for a 8 seater Toyota Van in addition.Here you find most ladies driving vans because it is more spacious and can seat a number of people. But the van consumes more fuel,so that is one thing to think about.Here we have no public transport and so we are forced to have 2 vehicles.