if it successfully disables vac, then no vac can't ban you because it's not running. If you fail to use vac chaos accordingly then expect to be vac banned.
Steps to make sure you run vac chaos correctly.
1. Run the program as administrator, to prevent any strange errors.
2. Once vac chaos is loaded, make sure the status's are all green and none is red.
3. If vac loaded is red that means vac is loaded, and there was an error with vac chaos.
4. If everything is green then hit load game on vac chaos.
5. Wait for it to launch mw2, then minimize or alt+tab to make sure vac status is still showing not loaded which will be in green.
6. With the new vac chaos I believe it's version 1.03, it will close mw2 in 1 second if vac is detected, to prevent the vac ban from occurring.
7. To open the console on vac chaos, when you're on the main menu where you see play and etc, press F2 on the keyboard, and it will show you the console.
8. GOOD LUCK, and HAVE FUN!!