Cocktail, please, but dress comfortably. San Diego's average temperature in July is 76 degrees and sunny. The ceremony will be outdoors on the patio, and the reception will be indoors, with air conditioning.
Mexican food. Tacos, with quesadillas for the kids. For dessert, we're doing donuts from Donut Bar.
If you'd like a lively beach community, Pacific Beach, Sunset Cliffs, Bird Rock, and Mission Beach are all fun areas and close to the venue. If you want to see a different side of San Diego, University Heights, Normal Heights, North Park, South Park, and Hillcrest are all densely populated with cool bars, breweries, restaurants, stores, and each have their own mini-downtown lined with storefronts and activities. (Peter & Molly live in North Park) Downtown can be pricier than other areas, as in any city. Gaslamp has a ton of night life. Little Italy has great Italian restaurants and a warm vibe.
Yes, as long as they dance and like donuts.
San Diego has the advantage of an airport located downtown near Little Italy, and being easy to get around in. If you're comfortable with ride-sharing apps like Lyft, you will likely save money over renting a car. Parking can be tough in some beach communities or downtown (and depending on whether your hotel/rental has a spot for you), but it all depends on the neighborhood.
San Diego is a tourist-friendly town. We set up a Things to Do page on this site to show off some of our favorite spots. If you have kids, there is the zoo, Waterfront Park, and El Prado within the city, but also Legoland and Disneyland are just a drive away, as well as tons of beaches.