Might just be repeating what has been already said but FLAC doesn't necessarily sound as pure as it should. Where WAV is lossless UNcompressed FLAC adds a compression, which cannot be done without sacrificing sound in one way or another, if temporarily (as is the case with FLAC). Its why a WAV file of a song is so much bigger than a FLAC of the same song. As was mentioned earlier the FLAC CAN actually be temporarily converted into a WAV for playback, but it doesn't necessarily have to be. A good program will do that (which it looks like cPlay might be a good choice).
Just from personal experience I like [url=http://www.videohelp.com/tools/PotPlayer]PotPlayer[/url] as my general music player and MediaMonkey as my library manager.