For nearly five months out of the year Disney's magic kingdoms are in a changed state. This annual alteration is important to note when plotting your vacation, especially for families attending for the first time.
The parks' transformation may come as a surprise for those expecting to explore the same classic Main Street, U.S.A the public knows so well. For many visitors, those iconic Disneyland and Magic Kingdom environments are the parks' real face, the images and scenery evoked when either is imagined. First time visitors should definitely consider how they want to first experience the world of Disney, preferring if possible to attend when the parks are in their traditional versions. Seeing the normal sights first gives guests a fine basis for comparison with the holiday overlays and cements the parks' historic appearance as the mental standard.
Finding Disneyland or the Magic Kingdom in their natural state can be a surprising challenge. Marketing promotions, special events and holiday overlays do add new flourishes to the resorts, and are often a visual treat to behold. But they may come at the expense of the 'normal' park experience, even supplanting famous attractions' usual selves with Halloween or Christmas inspired versions. Such is the case at Disneyland with the venerable Haunted Mansion, which closes in late August to become the Haunted Mansion Holiday inspired by The Nightmare Before Christmas, and "it's a small world", which receives a colorful Christmas overlay.
Be mindful, then, that you consider which version of the famous resorts you'd like to experience, especially for first-timers. In the world of Disney, holiday theming rules from September to early January.