How fun to be planning your 1st WDW trip. So to help answer your question, while there isn't one resort that will make it easy to visit each of the parks you are planning to visit, there is certainly a resort nearby for each of the parks.
Magic Kingdom: Hands-down the
Contemporary/
Bay Lake Tower are the closest; you can walk to the park or take the monorail. Runner-ups are the
Polynesian &
Grand Floridian, which offer both monorail & water taxi rides to the park.
The Wilderness Lodge also has water taxi rides to the park, but it always seems like the wait for those is a bit longer.
Disney's Hollywood Studios: You can take a longer walk to the park from the
Beach Club, the
Yacht Club, & the
Boardwalk or a water taxi.
Animal Kingdom:
The Animal Kingdom Lodge is right next door, but you do need to take a bus. It is a longer bus ride to the Magic Kingdom, though.
I've included links to the resorts for you to explore, but you might also want to visit www.allearsnet.com to see more pictures & information about the resorts. I'm also so glad you've been enjoying reading our answers to guests' questions; it is really an honor for us to be able to help.
Please let us know if we can help again!