Actually, Venus does not have the smallest orbital eccentricity among the planets in our solar system. That title goes to Mercury, which has an orbital eccentricity of about 0.2056, making its orbit significantly more elliptical than that of Venus, which has an eccentricity of approximately 0.0068.
In general, the planets in our solar system have low orbital eccentricities, with Venus having one of the smallest, but it is not the smallest. For comparison, Earth has an eccentricity of about 0.0167.
So, while Venus does have a low eccentricity and a nearly circular orbit, it is not the one with the smallest eccentricity.