Disneyland any day. The place is high maintenance, with great food, always cordial and nice employees, the rides are memorable, so many things to do apart from the rides... the list can go on on how confident and professional this place is.
Universal Studios is like a carnival with cool rides and a nice view... that's it. The place is ran like any carnival without any form of stress to be perfect like Disney, the food is mediocre, the employees can be rude (I've had this happen two times from the few times I've gone).
Just my take.