I've received this error on several songs that I've downloaded. Limewire's internal player can't play the file but if I use MusicMatch Jukebox it plays fine. Playing the song on MM doesn't "fix" the file, it still won't play in LimeWire. Usually I download another version of the song from another source. I find that the songs that don't play are a few Kbytes longer than ones that do, ie 'Song Version A is 2782K bytes' and doesn't play but 'Song Version B is 2779K bytes' and plays with either player.
Try using a different player on some of your songs that don't play. I'm betting the bad versions have some extra bytes of info added by the ripping program that Limewire doesn't understand so it can't play the file.