Hi Pamela,
Mickey's Very Merry Christmas Party (MVMCP) is a super fun event at the Magic Kingdom (MK). It does require a separate special event ticket to attend & only those Guests with the special event tickets are allowed to enter or remain in the park when the party begins. Click
here to see the official WDW link for MVMCP. Guests who want to spend the day at the MK & attend MVMCP on the same day, will need two different tickets - a regular ticket for admission during the day & a ticket to MVMCP for that evening.
MVMCP begins at 7:00 p.m. & lasts until midnight. Once party goers enter the park, they are given a special wrist band which indicates they have tickets to this event. Cast Members will be stationed at the entrances to the different themed lands. Guests who aren't wearing wrist bands for the event that evening will be asked to make their way down Main Street to exit the park.
If you are going to be in the MK during the day & staying for MVMCP that night, I'd suggest doing all the attractions & rides during the day & concentrating on the special events for MVMCP during the evening.
Dec 19th is the last day for the 2010 MVMCP. I checked the online calendar & beginning Dec 20th, Mickey's Once Upon a Christmastime Parade will become the afternoon parade & Holiday Wishes Fireworks will be performed each evening through Dec 31st. On Dec 30th & 31st in addition to Holiday Wishes at 8:30 p.m., Fantasy in the Sky Fireworks will be performed at 11:50 p.m. Be sure to pick up a Times Guide as you enter the parks to confirm as schedules are always subject to change without notice.
Wishing you many magical memories :-) Allison