Video files won't play properly!

The background: I tried to play the game Grim Fandango, only to be told I needed to download DirectX to play for some reason. Despite already -having- DirectX, I stupidly downloaded it again.

The problem: Most of my video files now will not play properly. Most AVI files seem to be fine, but MPEGs and MOV files are insane. The sound works fine, but the video is slowed dramatically, and in many cases the picture is flipped vertically (or possibly 180 degrees, I can't quite tell). I re-installed Nimo to try and fix this problem, but that didn't much seem to help. What else can I do? I can't enjoy my anime!

 

Update your codecs, you can download codec bundles from the internet, this may help, if not, your graphics card mightn't like the new DirectX version, an update of your graphics card drivers may help.

Best of luck

 

What codec package do you think I should download? I already tried Nimo...

 

It shouldn't really matter, try updating your Video card drivers