Hi Jen,
I have also stayed at the Hilton Bonnet Creek once when I had a conference there. It was a nice resort - very close to all of the Walt Disney World theme parks. Their pool complex is really amazing, with a built in lazy river. Be sure to check it out!
I think that whether you decide to purchase base tickets or to add the park hopper option really depends on your family and how you plan to tour the parks. Since you are going for four days, you could decide to visit one park per day and thus not need the park hopper option. Some people do like the flexibility of moving from park to park in one day. You might decide that you only want to spend half a day in Disney's Animal Kingdom, but a day and a half in Magic Kingdom Park, in which case you would need the park hopper option.
I suggest that you look at the
Walt Disney World theme park hours for the days that you are visiting. I do notice that Disney's Animal Kingdom is scheduled to close earlier than the other parks for the nights you are visiting. If you think that on your Animal Kingdom day you might want to leave and go to another park for the evening hours, you would need the park hopper option.
If you plan to spend from opening of the first park to open each day until closing of the last park to close each night at the theme parks, you will likely benefit from the park hopper option. If you plan to see one park per day, which over the course of four days will allow you to visit all four parks, you can go without the park hopper option.
I hope this information helps, Jen. Please do not hesitate to come back and ask if you have any further questions!