You'll probably find that you may have to go a whole lot deeper to make working back ups of games.
cd /dvd protection is big in teh gaming industry now. You wont be able to simply copy / back up a game (in all cases anyway).
You will need software to analyze the disc and see what protection code it is using. From there you can make the approriate settings in something like Alcohol 120 or Clone.
Doing just a straight back up with nero etc will only get you so far. You will be able to back up the game.....then even install the game from your new back up.
But when it comes to playing the game, you will often find that it asks you to insert the correct cd, even though you have your new back up in the drive. This is because of that protection code previously mentioned.
There are many other ways around this, but i'm not one to encourage them as most of these posts aren't about backups at all. I mean come on.... I lost FarCry while i was out jogging ^^