Think about turning south on US 395 in Reno and heading into Yosemite over the Tioga Pass (120). When you have seen Yosemite head for Salinas/Monterey. See what you want to see in San Francisco then head north to see some Coast Redwoods.
You can see some nice Coast Redwoods just north of the GG bridge at Muir Woods without heading all the way north to Redwood NP.
I would stay in Reno, Monterey, Oakland (ride BART) and Sacramento. I liked the HI hostel in Monterey.
I agree that you should not plan on paying parking fees in SF. Try riding in to the city on BART.

Second tomfuller's idea about 395 to 120 and over Tioga Pass. We've had a great snow year and the lakes and waterfalls will be outstanding. Passing through Walker River Canyon, Bidgeport and Lee Vining will be a great experience. Could also make a side trip to the ghost town of Bodie betweent Bridgeport and Lee Vining. There will still be lots of snow in the high county, but the roads should be fine.
You'll also have the giant sequoia's in Yosemite.
The best redwood grove, IMO, are north of Eureka on the CA Coast, Prairie Creek, Redwoood Nat. Park, Del Norte Redwoods SP
However, there are redwood groves near Santa Cruz if you don't have time to go north, Big Basin and Henry Cowell Redwoods state parks.

If you travel 395 south from Reno, top off your tank in Carson City at less than $4/gallon. I bought 2.4 gallons in Bridgeport on Monday for $12 ($4.999). The gas station in Yosemite may not be open by the time you get there.

> Should we go to Redwood National Park or
> can we stay closer to San Francisco to see the trees?

You can see SOME coastal redwoods in Muir Woods, which is a short drive from SF. However, they are nowhere near as spectacular as the ones further north. I'd recommend you see those REALLY tall ones on this trip unless you're short of time.

Be aware that the coastal redwoods and the sequoia redwoods are two different type of amazing trees -- you really should see both if possible.

If seeing San Francisco is a main point of interest, stay in San Francisco not outside. Part of enjoying the City is enjoying it in the evening, a tour will not give you that experience.

I agree with SAB. You could get a motor inn on Lombard St. (Cow Hollow Motor Inn, Chelsea Motor Inn, etc) that has free parking. It is so much more fun to walk the neighbors or take the local bus to see "the City".

An additional note to the Steinbeck fan: The Steinbeck Museum in Salinas (~30 minutes from Monterey) is very interesting.

With just 2-1/2 weeks I would get your redwood experience in the Santa Cruz area which is between Monterey & San Francisco rather than up north in Redwood NP. I agree with tomfuller about the Yosemite route from 395 south to 120 west and then onward to Monterey.

After Monterey I suggest you head north on Hwy 1 to Hwy 9 heading for Big Basin. You could get a room in Boulder Creek, Felton or Scotts Valley and easily do daytrips into Big Basin. It's a beautiful redwood forest, much better than nearby Henry Cowell. From here the trip to SF is only a few hours. If you want to stay outside SF city limits, Half Moon Bay on the peninsula is a good choice and better alternative than Oakland or the east bay.

Your biggest problem will be finding lodging near Yosemite. A good plan would be minimum 2 nights Yosemite, 2 nights Monterey/Carmel and 3 nights in or near SF. If you're driving R/T Detroit and want the 3 California experiences you're going to be on a tight schedule.

Thank you for all the suggestions, I am worried about lodging, we are having a hard time narrowing down what we want to do.

I like your suggestions Parrothead, thanks.

I liked everyones suggestions!