Let me tell you, it is a long drive to Yosemite National Park. I don't care which direction you come from; you are going to drive quite a way. But once you hit the major landmarks, you will find that every winding road was worth it.
Last year my family and I went to Yosemite National Park during spring break. We were in total awe with everything we saw. From the cold waterfalls to the breathtaking views, there haven't been many more beautiful places God has created other than Yosemite.
The accommodations at Yosemite all depend on what you plan to do. I would list prices but they are very subject to change. If you want to have a luxurious stay in the middle of some fascinating views, I recommend the Ahwanee Hotel. You will need reservations probably at least six months in advance and be sure to sell your first born because it is EXPENSIVE. Even the restaurants are pricey, but the food is great. We didn't stay here but we ate here for lunch and it was delicious.
If you want to get away from the valley crowd but still need a place to stay, check out hotels in Yosemite West or places near Mariposa. They are a little more secluded but offer good prices during the off-season. This is the option we took and loved it. The only hassle is that you have to drive at least 20 minutes of winding road to get to the valley but it is worth it.
If you want to "rough it" or half rough it, Curry village is the place for you. They have half-made tents with access to water and facilities, or bare bones places where you can set up your own tent and feel like part of nature. It isn't too far from the valley, either.
Speaking of the valley, this is where you stay if you want to be in the middle of things and want to have more centralized access to the community. Yosemite Valley is also pricey and hard to get short notice reservations but you will be within walking distance of several landmarks and all the restaurants like the Mountain Room (yummy!) the cafeteria and the general store. They also have daily tours, shows and historical museums outlining all the fun stuff about Yosemite.
Word to the wise: do not expect the general store to have everything you need. They will run out. They ran out of graham crackers. In the spring. All of ours broke on the ride up, so we went to get more and they were completely out.
Other than that, make sure to take in Tunnel view so you can see the monstrous El Capitan and Half-dome mountain sites. Bridevail Falls is also fun because you can literally be at the bottom of a waterfall if you wish. And if you venture down south to Mariposa, you will see Sequoias that are bigger than most anything on Earth.
I think Yosemite National Park is the perfect vacation spot for families who want to create lasting memories. I took every picture you see up there with a 5.0 megapixel camera. The nature did all the work.