Like others have said, 101 is beautiful and gets you away from the boring stretch of desolation that is I-5. Not as bad as say I-80 through the Nevada desert, but it's a long stretch of nothing but rice fields for hours.
If it were me, and I could take a while to drive down...here's what I'd do.
1. I-5 from Portland to Redding
2. Hwy 299 from Redding to Eureka and get on Hwy 101. Do yourself a favor, and take a short detour up to
Six Rivers Brewing. Once you get to 101, go north for about 10 minutes to McKinleyville. Nice place, with a view of the ocean in the distance, and more importantly a killer Kona Porter.
3. Head south on 101 down to Eureka, and you'll see the
Lost Coast Brewery on the west side of the road. Nice old building with some pool tables in the back and some pub fare. Definitely try the 8 Ball Stout and the Downtown Brown.
4. Head south on 101 to Fortuna, where you can visit the
Eel River Brewing Co.. They've got a nice patio, some good organic beers, and an appetizer of Calamari steaks that are to die for. Don't forget to throw a few horseshoes!
5. If you want to get a taste of Hwy 1, take it West towards the coast around the town of Leggett. Lots of windy turns here, so if you get queasy it may not be for you. However, if you endure the windy stretch of road you'll be rewarded with fantastic views of the rugged N. CA coast...and it will take you into Ft. Bragg, the home of the
North Coast Brewing Co.. They make some fantastic food there, and have some glorious belgians and strong beers on tap, as well as a good wheat and pilsner.
6. Heading south on Hwy 1, you'll come to the turnoff to Hwy 128. This takes you through Anderson Valley which is just a beautiful drive. As a bonus, in Boonville just off the highway is the
Anderson Valley Brewing Co.. Nice place to stop for a sample, a pint or a few bottles for later.
7. Keep heading south on 128 and this will eventually lead you back onto 101 just north of Cloverdale. At this point, there are all sorts of wineries about, and you are very close to Santa Rosa where you could hit
Russing River Brewing.
8. South of Santa Rosa on Hwy 101 is Petaluma, where you can visit the folks at
Lagunitas.
9. Just keep going south until you cross the Golden Gate bridge...and go to
Anchor Brewing!
EDIT: Google maps shows me: 445 mi – about 9 hours 17 mins from Redding -> SF via the route I describe. Totally worth it though...just get a hotel room in Eureka or Ft. Bragg.