About wedding photography and various camera parameter settings

You can just use 24-70. It’s easy to capture pictures. If you use 50, you will miss a lot of wonderful pictures.

The light should not be a big problem with 5D2. You can open the sensitivity a little higher. Anyway, this is not a photo that is too big. The sensitivity is higher and the maximum aperture is 27-70. It can be opened to 2.8, which should be able to cope with normal environments