Don't take the freeway!! That's rule #1. CA-1 and US-101 merge in Northern California, so you are really asking about from San Francisco to Leggett, CA. CA-1 is a pleasant drive. Slow, but that is to be expected. Fort Bragg and Mendocino are cute towns. US-101 runs more inland, through the redwoods, until you reach Crescent City and the Oregon border. You definitely want to be on US-101 when travelling up the southern Oregon coast....the numerous sea stacks offshore from Gold beach, OR are not to be missed. Stay on US-101 until you get up toward Lincoln City before heading over to Portland.
Will this be a one way trip or do you plan to return to SF?
>> Is Hwy 1 worth taking <<
Absolutely! The section north of SF is one of the most spectacular drives in the USA . . . well, also so is much of the section south of SF for that matter ;-)
It is quite a slow drive, so an overnight in quaint, picturesque, pricey Mendocino or the pretty but somewhat more plebeian Fort Bragg would work out well. Once Highway 1 ends at Leggett, the only through-road is Highway 101 which goes all the way to Canada.
If you have time, I would suggest staying on 101 to Cannon Beach or Astoria, then heading inland to Portland. It's only a couple of hours from the far north coast, and you'll see some gorgeous scenery along the north coast of Oregon.
Timing is important, though. With only a week, how much time do you want to spend in the big cities? Or is your week excluding city time?
We might extend it to 10 days depending on the sightseeing options. We want to see Alcatraz, but otherwise don't plan on a lot of time in the cities...unless there are other "must see" things.
would you take 1 or 101?
Highway 1 is a small picturesque highway that runs along the shoreline. There is where Bodega Bay of "The Birds" fame and Mendocino are located. Highway 101 is inland and goes through the traditional California Wine Country. Highway 1 would add a couple of hours more driving time and would be the choice of people who love scenic roads.
>> would you take 1 or 101? <<
As stated in my post 3 above, Highway 1 is well worth taking. But it is slow and will add more than just a couple of hours. There are many things to see along the way, including historic Fort Ross, Point Reyes Nat'l Seashore, Point Arena lighthouse, Glass Beach, many lovely state parks. You can easily spend a couple of days in Mendocino alone!
Hwy 101 is a pleasant moderately scenic inland drive that is much faster since a good chunk of it is freeway.
There are of course dozens of things to see and do in the city of San Francisco. Be sure to book your Alcatraz visit well in advance (directly) , as it is one of the most popular attractions in CA.
Check your Tripadviser message box, hobs. I have some information for you there. We took this SF to Portland trip in 2013 and really enjoyed it.