Right now, the spacebar only responds to presses directly in the center, and it's very loose and sits higher than the other keys. How can I make it not do that?
You could try to take apart your laptop and see if you can fix it yourself, however this will more than likely void your warrenty if you have one. If you can't fix it, sometimes you can find replacement keyboards for laptops online. What type of laptop is it?
Dell Latitude something. The Dell website isn't helping me determine which model exactly since all of the pictures are of the same laptop.
It normally says the model on the underside of the laptop. If you pick it up and hold it up high, normally around the battery area is where it says the type of laptop. If not there, then somewhere on the underside.
If DIY doesn't work, you should be able to get a replacement keyboard. My old Dell laptop once had an unfortinuate meeting with a Pepsi, and I had to get the keyboard switched out.