Hello Jennifer!
One of the greatest ways to experience Disney World is through the eyes of a 17 month old!!!!! OH, you are going to have an incredible time!!!
I would have to say the best Disney Theme Park to visit with a 17 month old is Magic Kingdom! All the attractions and rides are based on movies and Disney characters he will recognize. Just get your camera ready because he WILL be smiling from (mouse) ear to (mouse) ear!!! When you arrive at Magic Kingdom, go straight to Fantasyland. Every ride in this area is built for families with small children. Also, make sure you experience
Buzz Lightyear's Space Ranger Spin and
Monsters, Inc. Laugh Floor in Tomorrowland. To make it even easier for you to plan, click
HERE for a list of all the Magic Kingdom attractions. Please note that if the "age range" on the attraction says "pre-schooler", then it is something your son will enjoy.
I can recommend two Disney character dining experiences. If your son loves Winnie the Pooh, then I would suggest making Disney Dining Reservations at The Crystal Palace. Your son will enjoy meeting Pooh and all of his friends while enjoying a wonderful buffet. If your son likes Handy Manny and The Little Einsteins, I would recommend the Hollywood and Vine character buffet at Disney's Hollywood Studios. NOTE: It is HIGHLY recommended that you make dining reservations as soon as possible by calling 407-WDW-DINE.
I hope this helps in your planning! If you have other questions, please let me know!
Have a MAGICAL day!