Hi Elisabeth!
If you are staying at a Walt Disney World resort, the in-room babysitting service that is recommended by Disney is through
Kids Nite Out. (Direct link - http://kidsniteout.com/) They are not owned and operated by Walt Disney World. I have used their service with my two children and highly recommend it. Our sitter brought books and activities with her. You can give your sitter permission to take the kids out of the room and explore the resort and even take them to get dinner. They are not permitted to take them to the pool. We picked up a couple of quick service kids meals from our resort so the kids had food while we were gone. She took them for a walk and put them to bed when it was time.
Another option is to use one of three
Children's Activity Centers if your children are between the ages of 3 and 12. These are kids clubs with Walt Disney World counselors located at Animal Kingdom Lodge, Beach Club Resort, Wilderness Lodge and Polynesian Village Resort. They are open from 4:30pm-midnight and the price includes dinner.
If you are looking for a romantic evening out, I highly recommend the
California Grill located on the top floor of the Contemporary Resort. If you are there at the right time, you can walk out onto the observation deck and view the fireworks at the Magic Kingdom. Reservations are required. The two of you can head to the Magic Kingdom afterwards for some play time without the kids. It's a treat to be able to sit together on our favorite rides.
Have a magical day!
Leslie