While trying to install most drivers, I started running into problems, starting with my video card.
I have a GeForce 9500GT, which I tried to install using this driver, which is actually listed in your Supported hardware list for GeForce 9600GT. I extracted the files, and used the "Add New Hardware" wizard.
The driver seemed to install without apparent problem, but upon restarting, nothing would show up after the boot screen disappears. Even the monitor goes into Power-saving mode. I've had two ocassions where I'd even get a Blue screen with a "BAD_POOL_CALLER" error.
I've also tried installing other drivers: Realtek High Definition audio codec and the Intel INF Update Utility.
With the Realtek driver, it simply hangs on the "Installing the driver" phase (after the files are copied), slowing ReactOS down.
Intel INF Utility: The self-extract file crashes with a critical error (memory cannot be 'read'), and the contents need to be extracted, the extracted installer runs, but it doesn't seem to copy anything. It simply skips to the "Installation successful" screen. I know it doesn't copy anything, because the process usually takes a couple minutes under Windows.