Hi, Lucy!
While Disney does not provide transportation from other theme parks, you can certainly still head over to visit Mickey Mouse and all his pals!
You have a few options. You can rent a car when you arrive at Orlando International Airport. I always rent my cars ahead of time online with Dollar and pick my car up right at the airport. This will give you the flexibility to go wherever you want, including shopping, dining, or theme parks.
Your other option is to use taxis. A taxi ride from the Universal area to the Disney area will cost about $50 each way, so it can get pricey. You can look up Mears Transportation online for more information. At Disney, taxis are readily available at resorts and theme parks.
Your third option is to split your vacation at two resorts. After the first part of your stay, you can switch to a Disney Resort. Once on Disney property, you can use the internal transportation to get to all the Disney theme parks, shopping, and fun!
Tickets for the Walt Disney World theme parks can be purchased at the ticket windows at any Disney theme park, or check your
UK Disney website for ticket options.
Enjoy your visit to central Florida!