There are many ways to purchase paintings of Jesus Christ suitable for hanging and display, but websites such as JesusArtUSA and FineArtAmerica provide easy access to large bodies of work purchasable using the Internet. These sites host rotating bodies of work centered on Christ and his biblical life.
Art centered on Christ may take many forms and deal with many subjects. Some paintings illustrate biblical moments while others deal with purely fictional subject matter. JesusArtUSA deals with all classic Western depictions of Christ, especially in the American tradition, by variously depicting serious images such as the crucifixion and more heartwarming, family oriented affairs such as Christ juxtaposed into a modern scene of a family Christmas.
FineArtAmerica deals with more scholarly and existential depictions of Christ and also with reproductions of classical works from Western and Eastern Christian traditions. They sell hagiographic images of Christ, the Virgin Mary and other central figures in the Christian tradition, which can make for beautiful display pieces.
Ultimately, which images of Christ are fit for display over a home's mantle is subject entirely to the tastes of the individual. Some may prefer classical art while others may desire to pursue more contemporary depictions of Christ which indulge less in the tragedy of his life and ministry.