Age of mythology no cd problems

[g0wex]

Hope someone can help me, I have Age of mythology and want to run the game without putting in the cd each time, I have downloaded the file which has a file extention: aom.rar which I'm supposed to replace the original .EXE file from the game. What do I have to do to this file to make it work? probably me just being thick but widows does not recognise this type of file.
Cheers