you have to use flac plugin to play flack files in your player. the best player is Winamp 5.xxx (f.ex. 5.24)
here you can get FLAC plugin for winamp for free:
[
www.winamp.com]
to coverting files you can use : FLAC Frontend (freeware) FLAC to WAV files
or
Easy CD-DA Extractor (software) - very good (every audio file to every format)
it's very easy.