I would suggest trying VLC Player. Has Codec built in and will play almost anything. If you're interested, here is the link. It is Highly Recommened here on the Forums.
VLC media player - Overview
Filter these Bad extensions, go to Tools > Options > Filters > Keywords. Now add the following extensions including the dot. .exe, .rar, .wma, .zip, .mov. Click Apply and OK. This will clean up a Ton of Junk while searching. If you decide you Don't want to block a certain extension then go back and Unblock it. Try this, I think you'll like it.
What you are encountering are spam, and fake files. See Links below for more helpful info.
Always use
Bitzi to check video files. I ONLY download AVI Files
See:
Recognising Fake files
And for tips on finding good files, see:
How to find music.
Hope this helps.