Downtown Disney Orlando is is a rebuild/rebrand mode, converting it to "Disney Springs". It might officially be Disney Springs now, but any signs or other references to Downtown Disney are pointing to the same place.
DD/DS is pleasant when not too crowded or too much construction going on. It's a bit of a hassle to park there, so if you can get over there by resort transportation, go for it. I recommend the boat shuttle from Port Orleans French Quarter (or Riverside).
On the retail side, there's a giantic Disney merch store that's like several merch stores from the parks stitched together. It's actually kind of a cool walk through even if you don't intend to buy anything. There's also a Disney Christmas store that is open year round - they do personalized ornaments, stockings, etc.
There's also a really big Lego store that has all kinds of Lego kits on the inside, and several Lego statues of characters and animals inside and outside the store.
One of the flagships used to be DisneyQuest, a multilevel interactive games/tech experience. Fun if a bit dated, can't remember if it's closed yet. It's on it's way out to make way for an NBA-themed restaurant, bar, and store.
Some good restaurants at varying price levels. I dig the Earl Of Sandwich QSR, if nothing more than to watch them roll out the volume they do at their speed.
Wolfgang Puck has a DD/DS presence. His Express casual joint is great. Haven't been to the more formal one.
The big set piece restaurant is a fish/seafood place called the Boathouse. For many, it's a tradition to done at on every Orlando trip. Never been. It does look really cool from the outside.
There's also other family-friendly dining there. I think that's where T-Rex is. Imagine a mashup of Rainforest Cafe and Build-A-Bear with a dinosaur theme. Makes you a little mad you didn't think of it yourself, doesn't it?
There's also a couple of live entertainment theaters, like House Of Blues. (

<--- me after discovering twenty one pilots is playing HOB the night I get in town, but my flight gets in to late to run over and catch the show). IIRC, Cirque du Soleil has a theater there, too.
Folks who wax nostalgic about Downtown Disney will mention Pleasure Island, a series of bats under one umbrella and cover charge that covered a wide range of music and scenes. I'm a little too old to hop into cyphers these days, but remember joining in one at the 80s bar way back when. Sadly, Pleasure Island is gone now.
There's a running gag in this thread about a Princess-themed strip club at Downtown Disney. It doesn't actually exist. It should. It would be a huge moneymaker. But it does not exist, and there are no plans to open one on Disney property.