That's the Sierra tower and the one that is currently being refurbished. Just so you know.
Actually, it is now the Dreams tower. They changed the names a few years ago. When I was at DLR a couple of weeks ago, they had changed out about 2/3 of the windows in Dreams from sliders to the new stationary type (didn't stay at DLH).
Dreams = concierge lounge, DTD or pool view (and a few standard rooms because they have obstructed views), closest to DTD and the parks.
Magic = lobby tower, pool or standard view (most std view rooms have a parking lot view but good fireworks viewing and are nicer than the Wonder parking lot std view rooms IMO), closest to Goofy's, coffee shop (take-out coffee and pastries at the hotel), Steakhouse 55, and main gift shops.
Wonder = waterfalls and koi ponds in front, close to Croc's, a bar (Lost Bar?), a nice gift shop with glassware, and I've heard it's easy to park near it if you have a car.
OP: I would definitely ask for Dreams with DTD view!! It's AMAZING at the holidays. Last year, we had a view of the beautiful giant Christmas tree, right out our window. We loved the holiday music that came in when the sliders were open. However, the sliders are being replaced with non-opening windows so I don't know whether or not you'll be able to hear it now

. I liked the sliders--we opened them wide (they were huge!!!) and pulled our daybed over to watch the fireworks. I'm kind of sad that they'll be gone, but I'm sure the reno will be fantastic. It looked great in pics.
Edited to add:
Dreams.......old name Sierra Tower
Magic.........old name Marina Tower
Wonder.......old name Bonita Tower