Hi Bill! The deluxe resorts at Disney World are so wonderful that I, too, have trouble deciding between them, and I often stay at multiple ones during my vacation so I don't have to choose just one!
You're right that the Beach Club has a terrific location close to Epcot and Hollywood Studios and the fun Boardwalk area. The rooms are larger and brighter than those at the Wilderness Lodge and the Animal Kingdom Lodge, but the real draw of the Beach Club is the amazing Stormalong Bay pool. If your girls love swimming, I'd recommend this resort -- they'll have a ball on the humongous water slide! The pool also has a lazy river, a whirlpool, a sandy beach, and fun activities throughout the day, such as crafts, games, and line dancing.
The Animal Kingdom Lodge is such a unique and beautiful resort and in my opinion, everyone should stay in a savanna-view room there at least once in their lives! You'll never experience anything else like it -- being able to watch giraffes, zebras and Ankole cattle from your hotel room balcony is truly a magical experience. If your girls are crazy for animals, they'd love this resort. It is a little farther from the parks than the Beach Club, but I think the feeling of being a world away adds to the appeal of this African-safari themed resort.
The Wilderness Lodge has a great, rustic theme and a prime location close to the Magic Kingdom. I recently answered another question comparing it to the Animal Kingdom Lodge
here. While it's a nice resort, I personally prefer the Beach Club and the Animal Kingdom Lodge more, and would recommend those, unless it's extremely important for you to be near the Magic Kingdom.
Come visit me again at the Moms Panel if you have more questions! I'm happy to help!