I have Lassen to Eureka as 4.5 hours, Eureka to Santa Rosa as 4 hrs, Santa Rosa to San Fran as 1.5. Are those unrealistic? DS wanted to do Lassen because it looks like Yellowstone, his favorite. I guess we need to skip that and head straight to the Eureka area? We really don't need more than a day in San Francisco. I know that is a shame to miss but we really, really dislike large cities. We have been to Seattle twice (with locals) and the kids are miserable because of the traffic and crowds. (The kids are 20 & 17. LOL) I thought the Peanuts museum would be fun since it is DH's favorite but we may just find a place on the coast for 2 nights instead of so much driving.
Thank you so much for everyone's' advice, while I am researching as much as possible, first hand knowledge is so much better. All advice and suggestions are greatly appreciated.
I can't offer any advice on your specific destinations, but just want to throw out there that I have always had excellent luck using MapQuest. I have always found it to be pretty accurate. Of course I always pad the time to account for bathroom stops/gas/grabbing a quick bite to eat etc. One neat feature is it does account for traffic at different points of the day. if you put in your info at 8:00am Monday morning, it gives you the length of drive while taking into account the traffic at that time. You put in the same exact info at 2:00 in the afternoon and it gives you what the drive time will be then. It also tells you if the traffic is heavy at that time. I have used MapQuest for years and years and just discovered that feature last summer.
As an example I needed to find out how much time it would take us to go from our Lodge in Olympic NP to the lodge in Mount Rainier NP. I found out that the MapQuest time estimates varied greatly depending on if we were traveling on the weekend or weekday, or if it was 5:00 in the morning, 8:00 in the morning or 2:00 in the afternoon.
Last year we flew into Seattle, drove up to Olympic NP, then visited a lot of places on our drive all of the way down to Anaheim. Every single MapQuest estimate of time was accurate for us.
Keep in mind too, that what is a long ride for some is not for others. Also, while some may need days or a week at a place your family might be happy with less time. We live in NH and have done 5 National Park western trips. We fly out, rent a van and travel a LOT and then return our van to a completely different airport, usually well over 1000 miles from where we started!! While our trips aren't for everyone, they are perfect for us!
Have a GREAT time in Yosemite!!! I have been lucky to have visited twice and I LOVED it both times!! I have been to a lot of NP's and Glacier NP and Yosemite are tied for my favorite!! You are going to have so much fun!!
Oh and we did Alcatraz too a couple of years ago. One night in SF was enough for us. Different strokes for different folks!! We did Alcatraz, rode the cable cars and rented bikes and biked right across the Golden Gate Bridge! We also visited a few sites run by the National Park Service that are right there. Great time and lots of fun, but we didn't have a burning desire to stay much longer. Have fun!