Firstly Natalia calm down you're going to Walt Disney World and that's nothing to be nervous about :-) Secondly you've come to the right place, we're here to help you plan your trip as best we can so you have the most magical time!
One great place to start is right here, have a browse through the video section of the Moms Panel site to get some great tips, also look on the main WDW website, it now lists every restaurant, resort, activity etc and gives a brief outline of them. I also love looking at all the restaurant menus at a site called
www.allears.net choose dining then click menus.
For your dining plans as you arrive on June 20th you can make your dining reservations from March 22nd, if you're staying at a WDW hotel you can make all your reservations for your whole trip on that day too. There are many character meals that you can choose, if your daughter is into Princesses I would recommend Akershus Royal Banquet in Norway at Epcot or the beautiful Cinderella's Royal Table at the Magic Kingdom, this is the hardest reservation to get so if you choose to dine here make sure you phone 407-939-3463 on March 22nd at 7 a.m. EST. If she loves the Pooh Characters the Crystal Palace in the Magic Kingdom is great or how about dining with Playhouse Disney Characters at the Hollywood and Vine in Disney's Hollywood Studios. All the details for all these meals can be found at the allears website.
As for Fantasmic and PhilharMagic, Fantasmic is a free fireworks and laser show at Hollywood Studios, there is a dining package available to get reserved seating, again information can be found on the site listed above. PhilharMagic is a show in Magic Kingdom and is one of my favourite things to do, it's in a theatre and you wear 3D glasses, it's fantastic and you will love it. No reservations are needed just join the queue!
I hope I've helped a little, please feel free to ask more questions as we love to answer them.