hmm sorry, first i forget to mention that it's the PC version of the game.
As StarEye said, if the site own the permission from the authors/company to host the game then it's legal.
BTTR host lot of game in this way.
The music of Wipe Out XL on PC are stored as file and not as CD Audio track.
Of course using Daemon Tool or a similar tool handle to play the game with the music but it doesn't solve the FPS max problem and also i prefer to host the game as file on my hd.