I suggesrt yo get SCID
http://www.chess.com/download/view/scid-361
Download free "Chessbase light" from www.chessbase.com
You will find it a great tool for all pgn files! Works with Windows XP/Vista/7
Here are the updated links, though I still cannot open any of my saved PGN files from Chess.com:
https://en.chessbase.com/post/new-chebase-light-2009-know-everything-
i would like to open some game once i've downlaod them but my windows xp does not recognise the pgn format, is the something i can download to open the files?