Viewing .mpg video files in browser?

I am hoping one of you awesome Macsters can help me to regain a feature that was recently lost whereby I could single click on a .mpg file on a website and Safari would open up a new window then begin playing the file. I recently had to perform an archive and install of my OSX and as a result Safari no longer plays .mpg files from within the browser as it used to. Instead, Safari now downloads the file to my HD then uses another app(I use MPlayer) to open the video file. How can I enable Safari to once again play .mpg files from within the browser like it used to??? Is there a specific plugin that is responsible for this feature that I need to reinstall??? I have the plugins for WindowsMediaViewer, RealPlayer and ShockWave Player installed and they seem to work fine. I am a bit behind the times in that I am runnning OSX 10.2.8 snd using Safari 1.0.3 Until I have the opportunity to upgrade can anyone help??? Peace out . . .