Which wineries should we go to on our honeymoon?

Congratulations, Kip! 

In Calistoga proper, Castello di Amorosa is amazing.  It's a castle with its own moat!  Great wines and you can schedule a private tour of the place.  They, and pretty much every winery, will educate you about their wines and wine in general.In Napa, I really like Artesa Vineyards & Winery, really gorgeous spot and good wines across the board!  

If you really want to see the process, take a cave tour at Del Dotto Estate Winery & Caves, which is a similar experience to Castello di Amorosa.

For food...

• This isn't the fanciest of places, I'm going to suggest my favorite spot that's great for lunch: Gott's Roadside! I love them! They have a location in Napa, too. Their seared ahi tuna burger with Asian slaw and wasabi aioli on egg bun is my favorite. They also serve beer and wine from local wineries. Order and pay inside, then grab a seat outside to take in the beautiful wine country sun.
• For breakfast or brunch, Boon Fly Cafe is one of the most popular spots in Napa.
• ad hoc serves a great prix fixe brunch on weekends. If you're familiar with Thomas Keller or French Laundry (which is actually down the street), well, this is one of his spots! Also great for prix fixe dinner. You do have to make reservations for this spot.
  

For fun...

• Take a walk in downtown Yountville on Washington St. Search for The French Laundry in your GPS and go from there (this is also where ad hoc that I had previously mentioned is). There's a beautiful garden/park adjacent to the restaurant and that's a good place stop off for a walk and take some pictures.
• Old Faithful Geyser of California: Grab a picnic lunch and head here to see the geyser. Good spots to grab lunch to go are at Buster's Southern BBQ or Palisades Market, both close to the geyser in Calistoga.
• Downtown St Helena (California) is also great to walk through for some shopping. Great boutiques and little specialty food stores.

By the way, Calistoga is known for their spas because of their hot springs and mud baths, so maybe you can have a spa day there.  These are the top three spots there:

• Solage Calistoga
  
• Indian Springs
  
• Lavender Hill Spa
  

Solage and Indian Springs are also highly regarded resorts, so those are possibilities for lodging.  Another really popular one in the area is Auberge Du Soleil.

If your wife likes surprises, keep the hot air balloon a surprise :)

Have fun and let us know where you end up going!

Castello di Amorosa