Computer Room Design

I need to draw floorplans with automatic dimensioning and square footage displayed in each room. Curved walls is also required and the ability to export to bitmap or jpg.
Does anyone know about an easy program to use, I don’t need 3d or furniture etc capabilities.

I know the dimensions and square footage of my new apartment but I haven’t moved in yet. I also know the dimensions of the furniture I’m thinking about buying.

I want to use 3D software to layout the entire room, so that I know what to buy. That way the furniture can be delivered the day I move in!