I think they would call you (and me) "very particular about the details". There are probably some better phrases for our condition 🙂
I can't tell you the resolution, but I had a 17'' monitor. It was probaby 1024x768, like you said.
I did a test run to my test center. They would NOT let me into the room, see the monitor, or check out the mouse. They told me there was a picture of the setup on the prometric, but I could not find it. Hopefully, your test center will allow you to check out the test area.
But let me describe the test center as best I can. The center was clean. It was a very professional environment (because I think ADA keeps Prometric on a short leash). The computers were functional, clean, and in good shape. Each test room seemed to have about 20 workstations. They were small cubes like you typically see in college libraries. The rooms had cameras, but I think globes covered them (like you see in Vegas and casinos). One last note: the mouse had a scroll wheel, but it did NOT work on the actual DAT...but it does work on TopScore. My suggestion: don't practice TopScore with the scroll wheel.