Why doesn't the touch work on my ipad
The iPad's touch screen should always work, unless it froze. Try and restart the iPad (hold down the button on the top edge, close to the camera lens until the iPad turns itself off, normally a few seconds). If it doesn't work after a restart, you may need to reinstall the system, which you can do from iTunes (attach the iPad to your computer, open iTunes and choose 'Restore iPad' - you need internet connection to download new system). Have iTunes back up your iPad before restoring it, if possible, or data will be lost.
If none of this is possible, you may need a repair at a service centre. Good luck! :)