After mounting, run the installer, or if you really want to, run autorun and then open the installer for that burst of nostalgia when it comes to getting a new game from the 2000s. If you're using an iso, just get WinCDEmu, a very simple not shady program that makes virtual iso drives, works like a charm. I do not use this copy of the game and got mine elsewhere, however, I will give you instructions that should allow to play the game. If you look in the right places, there are more solid copies of NR2003 that can be downloaded and used, seems MyAbandonware's version has flaws.
