Windows Vista users may be disappointed that there is no driver support for the old game port (the 15-pin port, often located on a sound card). This means that any old gamepads and joysticks that connect using this port would normally be out of use with Vista.
The 15-pin game port will look similar to this image:
At the moment only USB gamepads and joysticks are supported, but this means many high quality input devices will be obsolete (such as the Microsoft Sidewinder series).
Fortunately, there are some very clever user modifications on the net that will add the old Windows XP game port drivers back on to your Vista PC.
The most successful game port driver pack is available for download/support on the Creative Labs forums here. If you want to download the software directly, then you can do so from FileFront.
You need to use these drivers on the "Unknown Device" or "PCI Input Device" that may show in Device manager, which is actually the game port. You can then install the old gamepad control panel and add/configure the new input device. This is exactly the same process as under Windows XP, but fully compatible with Windows Vista.