Semi-formal, but whatever you feel great and can dance in!
Here! https://www.zola.com/registry/supplee (or check out the "registry" page of this site)
The best answer is walking! The entire city is incredibly walkable. Outside of that, there are plenty of Ubers/Lyfts, trolley tours and free public transport at https://gosouthsavannah.com/visitor-info/transport/public-transport.html
YES! And one of the many reasons we chose Savannah as our wedding destination. Most bars and restaurants even offer to-go drinks. Only rules are that it has to be held in a 16oz cup (no bottles, mugs, flasks) and must be in the parameters of the Historic District
We love your kids (they're so cute!), but the wedding will be adult-only : )