What is your 5 year old like? I think the youngest kid often holds back the group (unless you're willing to separate). Will s/he go on "thrill" rides like RSR, BTMRR, etc.? My DDs were both a bit hesitant/sensitive at 5 years old, so we stuck to these low-key rides/shows:
DL: Dumbo, Autopia, carousel (skipped all the dark FL rides given their sensitivity), the Railroad (though the dinosaur scene scared my 5 year old), Go Go Gadget coaster, Princess/Fairy/Toontown meet & greets, and the parade. Fireworks were too loud so we left the parks each day before fireworks. FYI, I had DH take the youngest a few times so I could ride Space Mountain, Star Tours, etc.
DCA: Bug's Land rides, some Paradise Pier rides (one DD loved Goofy's at 5 because she could see the tracks and anticipate the dips/turns, the other DD hated it as it's so jerky), Ariel, Disney Jr. show, Animation Academy, parade,
If you're not targeting the E-tickets, I don't really think order matters except for Dumbo (go early as there isn't a fast pass and it's a slow loading ride) and some of the Meet & Greets close early (I think Pixie Hollow closes by sunset?).
Have fun!