Hi Jill,
If your daughter loved Disneyland, Disney World is sure to be a hit!
With either a 9 or 10 day trip, you can certainly fit in a lot of Disney Magic. As far as deals go, it will depend on when you book and when you travel. Disney is currently running a great deal that when you book a 4 night vacation, you get 3 additional nights free, click
HERE for more details and valid travel dates.
While there are many rides and attractions that are in both Disneyland and Disney World, things like the Animal Kingdom and World Showcase in Epcot are going to be so exciting for your family to visit. Your pre-teen daughter may also enjoy the Typhoon Lagoon Waterpark, Winter Summerland Miniature Golf, or catching a movie at Downtown Disney.
Have a great vacation!