Driving in LA is very easy. Pick up a Thomas Guide if you're unsure of yourself, or make sure you have a GPS in your rental. As others have suggested, park at the Hollywood & Highland complex near Grauman's chinese theater. There is a garage under the complex.
Be aware that there are a variety of characters in front of H&H that are eager to pose for pictures with your family. Please be aware they are not free. They are not employees of any business in the area. These are just people in costumes who are there to pose and ask for a "contribution." You may want to warn your kids in advance so they don't get excited when they see Tigger or Batman. I was there with a friend and we got sucked in more than once by Mario and Luigi because her son was a HUGE Mario fan. I think he ended up making about $20 off us in the course of the afternoon.
This area is also where all of the busses load and unload. You'll find lots of tour sales folks out there and they will approach you. We actually walked around the corner (west of the theater) and visited the main sales office for one of the companies. We negotiated our price down by $15 per person for a tour. If you do decide to do a tour once you're there, I highly recommend an open-top vehicle. The enclosed van/bus does not allow you to see very much at all. The big double-deckers are fun, but they will only do main roads around Hollywood. The smaller, open-top vans will go up into the neighborhoods and are the best tour for your money.
I also recommend keeping the WB tour. I did it a few years ago and loved it.
I second the suggestion of a visit to Venice Beach. Not only is it a fun place to people-watch, but a great place for CHEAP souvenier tshirts! For actual "beach" visit, I recommend Huntington Beach - a very easy drive from
Disneyland.
