A:Answer This monitor will work with any operating system, so it works fine with Vista as well. The white cable is a DVI cable and can be used to connect to computers that have DVI ports. The fact that you're using the blue cable (VGA) doesn't matter and will work just as well as DVI.
It sounds like the issues you are having are related to your computer. Especially if it's an older computer, you will have issues playing newer titled games. I suggest having someone look at your computer and see if anything can be done to speed up its processing and possibly upgrading the computer/components.