AFAIK WinAmp's very good. If you like, you could also try playing the file with VLC player...if that fails as well then I'd guess it's just a crappy file. You can download VLC here, choose a close mirror for download.
http://www.videolan.org/vlc/
Did you preview the file while downloading? It's a good idea to preview after about 10% download, just to check that things look ok. Also, always check a video file before download with Bitzi. Other users might have rated the file & in that case you'll have some idea of it's content & quality.
How to use Bitzi