It is a combination of things:
- All the classic video games. Everything from the original space invaders and donkey kong on. My kids discovered a love for Q-bert. I remembered how much I loved (and how bad I was at actually playing) Joust.
- Many of the current video games and other games (like sports games) you'd find in an arcade. Just, instead of paying to play each time, it's an all-you-can-play thing (you press a button on each game that acts like entering coins or whatever).
- Immersive video games. Some of these are really good - the Pirates of the Caribbean game is as good as anything else I've seen, and lots of fun to play as a family/group. Some are really dated - the Aladdin game uses a head-mounted display system from the 1990s, which compared to the Oculus Rift is just pitiful (but shows you how long it took to make real progress in VR systems). There's a virtual jungle cruise game that's fun (you ride in a simulated raft that you paddle). Cyberspace Mountain lets you design a roller coaster and then ride it in a simulator (think Sum of All Thrills, but a little bit different). There's a bumper-car game where you shoot balls at the other cars to make them spin. I know I'm forgetting at least one.
- They also have a "create" zone where there are animation classes given several times a day, and you can create toys and CDs (some for an extra cost). There's a small (and not very good) snack bar, also.
As others said, though, it's dated, and honestly is not being kept up well. There's a whole lounge on the 4th floor sitting empty, and the food offerings in the snack bar are really pitiful. I noticed lots of small things in need of maintenance/repair/paint. Honestly, it's not being kept up to the Disney standard. But, it's still a lot of fun. Our family had just a few hours there on our final day this last trip, but we could have easily spent several more. I would recommend going if you have kids who like video games, or like them yourself.
If you care about history:
DisneyQuest was created in the late 1990s (I believe it was '98), and was intended to be the first of a whole chain of DisneyQuest locations that would be located in all sorts of cities. I think they opened one in Philadelphia or maybe Chicago briefly, but shut it down shortly after - people weren't willing to pay Disney vacation prices for just the one experience, and it was basically a giant flop. They put a lot of work into developing the original VR games that are there, and they represented the pinnacle of VR technology at the time. The Orlando location has made enough to be profitable enough to continue operating. But, the model was supposed to involve those original games (and new ones continuously being developed) being installed into dozens of locations, and with only the one operating location, they could not justify R&D costs to develop new games. They did install the Pirates of the Caribbean game a little later, but other than that, there was nothing else significant added in all the years since (they have brought in new arcade games). They maintain things enough to keep it operating, but nothing more.
At one time, it had even more - like a remote control car game on the bottom floor, a comic swordfighting game (parts of those are still sitting empty, along with signs that point to the no-longer-existing ride), and an Aladdin genie "experience" on the initial elevator ride (originally, even entering the building was an experience). Instead, it's been left to just slowly hang on since then. They still get people coming in, and I still find it a lot of fun. It shows you something by how unique many of the immersive games are even today that they did a good job with the original design of most rides, even if the overall concept didn't work out. But, the current state is pretty sad if you knew the original, and the idea of what it was going to be at the time.
There were recent plans to convert the building into an NBA experience or something (and it was supposed to be closed this year), but those evidently fell through, so it's again in limbo, just hanging in there. I am not sure there are any concrete plans to close at this point, but it's widely understood that if a good option for another use of the building comes up, they'll be closing it down.