Playing Video Files in Vista Windows

I'm new to Vista. I just bought an Asus CM5570 with Pentium Dual Core CPU, 2.60 GHZ each, 6GB Ram, and 630GB HDD, running Vista Home Premium 64 bit OS. I've been previously on Windows XP Pro. In XP Pro I could open any video file, double click on a video, and a window would open playing that video with sound. How is this done in Vista?

Download this Vista codec package and install it in the C:\Program Files x86, next get x64components and install them into C:\Program Files and reboot the computer. After that you are ready to play any video files using Windows Media Center or Windows Media Player. Just double click the file, same as in the XP.

For Vista 32bit use only codec package without x64 components.

It would help to know what happens when you double click on a video. Where does it go wrong?

Generally:
First thing you need to do, is make sure you have a video player that can play the videos you're interested in. Windows Media Player plays the most common formats, so unless you have an uncommon video format, this shouldn't be a problem.

Next, you have to make sure that the hardware is "installed" properly on your computer (this requires drivers). This needs to be done with every new operating system. To obtain drivers (in this case, you want one for your graphics card and sound card), you need to find out who the manufacturer's website and download them (and then run them to install them).