Most CartoonNetwork.com games require Flash. If you don't have it, you can download the free Flash plug-in here.
This will allow you to play the majority of our games library. The remaining games require the Shockwave plug-in, which you can download free here.
If you still can't get the game to load, you might be running ad-blocking software that prevents the game from loading. Turn off your ad-blocking software (or ask your parents to help you turn it off) and then try loading the game again.