First, don't worry about a thing. I know that planing a vacation at Walt Disney World can seem overwhelming at times, but we here at the WDW Moms Panel are here to ease all of your worries and help you with everything you need!
You chose a wonderful resort to stay in during your vacation.
Disney's Polynesian Resort has a wonderful pool, delicious restaurants and is close to the parks. You will even be on the monorail line for Magic Kingdom and Epcot!
Here are my top five tips for having a great time, but not stressing yourself out.
1. Buy the Magic Your Way Park Hopper with Water Parks Fun and More.
2. Visit the park with Extra Magic Early Hours in the morning and the park with Extra Magic Evening Hours at night. Since you are staying on WDW property, you can take advantage of the Extra Magic Hours. This will extend your day and allow you more time in the park.
3. On your first day at Walt Disney World, go to Downtown Disney, and make an Advanced Dining Reservation at T-Rex 180 days before your check-in day. Call 407-WDW-DINE to book. I suggest making your ADR for T-Rex for lunch, then go to your resort, check-in, go to the pool and then head over to Fort Wilderness Lodge that night to eat at Whispering Canyon Cafe (which will also require an ADR.)
4. Since you will have four full days left, you can experience each of the four parks. Since the water parks open a bit later than the other parks, you can visit one park in the morning, then leave around lunch to "hop" over to the water park. You can then "hop" over to another park that night.
5. Make all of your ADRs in advance to ensure you can eat at the dining locations you indicated.
You can fit it all in, you just need to plan it out in advance. Please let me know if you need any more help as you plan out your magical vacation! It is my pleasure to help!