Get VLC - (click on link) _ (choose nearest mirror site) with its in-bult codecs & this will solve your problems. To see what it can do see the following http://www.videolan.org/vlc/features.html good for either audio or video streaming, can change skins, recognises many audio formats, etc.

Introducing a heavier media player for LW would slow it down. It already uses most of its resources for its normal functions of searching, downlding & uploading, etc. The audio media player often suffers. A video player would struggle even more. It's not really such a big deal using the launch or preview button for video files.

If you thought LW would have video playback, then it sounds like you didn't get LW from the official site. Nowhere on their site does it mention anything about video downlds or playback.