This question is much tougher than it seems to be on the surface. I'm going to go against conventional wisdom here and suggest that HS is the better option for her. Epcot is the superior park of course, however, a 5 year old girl won't find as much fun at Epcot than she would at HS. Between the Little Mermaid show, Beauty & the Beast, the Frozen Sing-a-long, Honey I Shrunk the Kids playground, Fantasmic, Playhouse Disney and all those characters, the characters in the Animation Courtyard, Buzz & Woody, and TSMM, DHS is better overall for a young girl. Not many 5 year old girls are going to like Sum of All Thrills and Test Track. Most won't much enjoy Spaceship Earth. So we are pretty much down to Soarin' and Nemo. Sure, there are some nifty character greetings in the World Showcase, but overall, Epcot is more oriented to older kids and adults. Especially if she is going during the FW festival.