I think for weddings you want a fast medium format system and Portra 800, though if you already have nice lenses for the full frame 35mm format I'd stick with 35mm and Portra 800. Portra is nice because if you need 1600 or 3200 ISO you can get the film push processed. If you like black and white you might try TMAX 3200 film. The F5 would give you a similar feel to the D3, but the N80 will work just as well and be cheap and light (there's no difference between cameras besides weight and frame rate.) If it's outside on a bright sunny day you can try Portra 160NC or VC depending on the saturation you want. Just experiment until you find films you like.