PPCGeeks - Phone Call App?

This might sound like a ridiculous question, but is there a phone call app for touch pro2? My mother is smartphone handicapped and she can't use the touchscreen for her life. She keeps dialing wrong numbers, clicks on my contacts by accident and so on... I was wondering if there was an app that I could leave on that would only allow phone calls (only the keypad shows up and nothing else) or an app that would lock all features/contacts of the phone except for phone call use. If anyone has any suggestions, please help. I don't want to deny my mother the use of my phone but this is driving me crazy!