I wouldn't recommend using VLC media player for flv files because that player is not capable of fast forwarding to any point in the video you need to watch the video up to the point where you want it to. Basically you can't skip anything with the VLC player with FLV files. The VLC player is great for everything else but sucks for FLV files.
FLV media player as Lirange said is much more better suited for FLV files
http://download.cnet.com/FLV-Player/...-10467081.html
FLV files will only work in Windows Media player if you have the right codec installed for it. You can download ffdshow and install that and in the codec settings make sure FLV1 is not set to disabled then load it up in windows media player.
http://sourceforge.net/projects/ffdshow/
I would recommend downloading FLV media player as ffdshow is a little more complicated to setup but if you can setup the ffdshow codecs you can have flv files playing in windows media player.
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