Hi Jennifer!
How wonderful that you have family members that you can stay with! If I had family in the Orlando area, they might have to change the locks! You can absolutely stay at a Disney Resort (any of them) for one night. I think it's a great idea to experience staying on-site, even if it's just for a night.
If you are looking for the most economical options, I'd recommend one of the Value Resorts. You have four well-themed properties to chose from, including All Star Music, Movies and Sports and the Pop Century Resort. If you'd like a sneak peak of each of them to help you decide, you can log onto
www.allears.net for some fabulous photos. If you'd like to splurge a bit, and upgrade to a Moderate Resort, I'd recommend getting one of the newly redone Pirate-themed rooms at the Caribbean Beach Resort. The rooms are amazing, the resort has NINE pools, and the main pool has an amazing Pirate Ship splash area with slides and water canons.
Have a great trip!
Tanya