If you are not in a hurry suggest Westbound from Winters (west of Davis) over to Napa Valley then to Sonoma Valley. There are various good back country roads that are fairly quiet. From Petaluma south there are a variety of bike paths and good roads leading to Sausalito and the Golden Gate Bridge. There are also roads that should be avoided due to heavy or high speed traffic..and sometimes both. Avoid the temptation to cut the corner from Vallejo to Novato on Route 37 is one.
Another option is to make your way to Concord or Walnut Creek and jump on BART to SF...or take the ferry from Vallejo of course.