ANSWER: The short answer is yes. If you buy a touchscreen monitor and connect it to your Windows 7 PC then it should just work, although there may be a driver to install.
For 3D viewing you'll need a 3D-capable graphics card (and the 3D glasses it comes with), plus a compatible monitor.
Be very careful when selecting a monitor, however. 3D-capable displays often have a refresh rate of 120MHz or more, which explains the need for a special graphics card. For more information and advice, visit the 3D Vision section on nVidia's website.