We're planning on flying in the Thursday before and doing Legoland on Friday and DL on Saturday. If I take off anymore time than that my boss is likely to end up in a psych ward, especially as I'll be incommunicado for the majority of the trip.
I've not done Legoland in CA, but we did the one in Windsor in '02 and it was awesome! In addition to rides, they had the most amazing displays built entirely of legos. My then 9 & 11 yo boys were even interested in them!
Before the cruise my husband has it in his head that it would be cheaper to fly to Las Vegas and rent a car and drive to the port. My sister may be changing jobs, so she probably won't be able to take a lot of time off before the cruise and we won't leave any earlier than that Friday night.