Time: I would highly recommend coming in early March. The weather around here is gorgeous in the early spring and the mustard flowers are blooming so the vineyards are covered in yellow flowers. Another bonus, the barrel tasting weekends:http://www.wineroad.com/events/barrel_tasting/8. Anyone who loves wine and wants to try a great variety this is the best time to visit (two weekends to choose from). You have access to over 150 wineries for three days straight all for $35.00 (total). Amazing right?
If spring doesn’t work I would suggest fall. Harvest time brings around several fun festivals in the area and the weather is also gorgeous. Mid-70’s, no rain and the leaves start to change. The crowds aren’t too bad compared to the summer months and if you visit the local coast the fall lends the best time of year to do so (surprsingly better than the summer).
Hotel: With that price range you are going to have a hard time staying anywhere within Napa Valley without some amazing groupon once in a lifetime deal. Most hotels start around $300 a night. You can stay in Napa (city) for mid-200’s and if you are lucky just around $200. If you come over to Sonoma County to Rohnert Park, Petaluma, Santa Rosa (across the hill) you can get a hotel for high $100-200. So it would be cheaper but you would have to drive either to Napa Valley (45 mintues or so) or Sonoma (30-35 minutes).
Food: For Napa Valley there are several amazing places with middle of the road pricing.
-Bouchon is my absolute favorite (Yountville). It is the less presumptuous brother to the French Laundry. Even if you don’t eat there stop in and grab some naughty things at their bakery.
-Rutherford Grill (Yountville)
-Pizzeria Tra Vigne (St. Helena). I used to work there several years ago. The food is absolutely out of this world.
-Villa Corona (St. Helena, been told this place is amazing. Although Armadillo’s is good too right up the street).
-Gillwood’s (St. Helena. A small cafe with amazing breakfast and brunch. Used to eat here every Sunday when I was in college).
-Guigni’s (St. Helena. Small hole in the wall sandwich place. Grab one and find a pretty place to eat…perhaps at V. Sattui Winery right up the road. Definitely get the Guigni “juice”).
-Cindy’s BackStreet Kitchen (St. Helena. If for no other reason simply go for dessert).
Sonoma (town of):
-The Red Grape
-The Girl and the Fig (Amazing)
-Hopmunk Taven (pub food, great music)
-Rancho Viejo (near the main square)
I can amend suggestions depending on where you end up staying. Like I said you won’t be able to stay “in” the Napa Valley with those prices but can stay within a relatively reasonable drive.