With four major theme parks, two waterparks, 22 themed resorts, other attractions, and a total area the size of Boston, Walt Disney World is a vast destination. Start with this overview.
The original Disneyland is in Anaheim California, and opened in 1955; it is now called "Disneyland Resort" and has two theme parks, Disneyland (often thought of as "The Magic Kingdom"), and Disney California Adventure. There are now also Disneylands in Tokyo, Paris, and Hong Kong.
In choosing your time to visit Walt Disney World (or Disneyland), you want to balance four factors: crowds; weather; park hours; and special events. Busy times of year do have some benefits, such as extended evening hours, extra night parades and fireworks.
Disney vacation cruises are generally considered a top family cruise choice, with excellent kids programs and top-quality entertainment. Nursery care is available too (at an extra cost.) Cruises regularly leave from the east coast of Florida, not far from Orlando; many people do a combined Disney Vacation, i.e. theme parks-plus-cruise. Mickey's cruise ships ply other waters, too: the Mediterranean, Northern Europe, Mexican Riviera, Alaska...
"Family Adventures" are typically small-group tours that offer families a best-of-the-best itinerary in top locations, with all details handled. Disney has entered this niche market, and offers trips to London and Paris, Italy, Costa Rica, Yellowstone, Canadian Rockies, and more.
Disney World goes all out for Christmas. Holiday lights go up in November; every park is beautiful but Disney's Hollywood Studios has the most wattage, with the spectacular Osborne Family Spectacle of Lights. You don't need more than your regular park pass to enjoy the Spectacle of Lights, or the Holidays Around the World at Epcot; but you do need to buy special tickets -- and buy early!-- for Mickey's Very Merry Christmas Party in the Magic Kingdom, and for the Candlelight Processional in Epcot.
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