Howdy Kellie! So so so many things to think about.
I'm so glad you are considering staying in a Deluxe Villa during your first trip to Walt Disney World! FABULOUS! You will have the opportunity to have your entire party in one Villa and be able to enjoy every magical moment together. The kitchen in the 1-Bedroom Villas and larger is great and will help you keep your food costs down. You will also love having the washer and dryer!
Based on what is important to you, I'm thinking
Disney's Saratoga Springs Resort and Spa might be a perfect resort for you.
Saratoga Springs is one of the most economical Disney Vacation Club resorts. The Villas are beautiful and very spacious. It's conveniently located near Downtown Disney and offers Treehouse Villas if you are interested in surrounding yourself with lush trees in a Treehouse setting.
If Treehouses aren't your style, I would recommend that you request a Villa in The Paddock. The pool at The Paddock is fantastic!! It has a 146-foot-long slide that flows from atop a water tower. It's great for your kids because it has a gently sloping, zero-depth entry point and they will love the aqua-play area.
Regarding transportation, I know many people prefer to stay in the Treehouses only if they have their own vehicle but there is a shuttle that runs throughout the resort and, like all of Walt Disney World, you will find the great Disney transportation regardless of where you stay.
I'm so excited for you!!! Thank you for your question and please let me know if you need any further information as you plan your vacation. Have a magical day!!