We went from Sunday 21st to Friday 26th this year. On the Monday to Thursday the Disneyland Park closed at 9pm. We went home Friday but it was open until either 10pm or 11pm that day. The Studios closed at 6pm, except for Thursday when I remember it closed at 7pm. My brother-in law went for the start of Halloween season and the park shut earlier midweek then, either 6pm or 7pm. Obviously our later hours were because it was school-holidays that week for a lot of the UK. The following week was school-holidays for France and the remainder of the UK so it would have either closed at those times or maybe even later. As miffy7 said, it's always 1am on Halloween.