When the problem you describe occurs, it is usually because of a recent application that was installed to your device. You will need to reload your device's software. You have what is referred to as a "bricked" or "nuked" device. Follow the instructions found at Crackberry.com at http://crackberry.com/blackberry-101-lecture-12-how-reload-operating-system-nuked-blackberry and you should get going again.
Thanks to the community for your replies.
If you have any problem with reloading the software. Please call 800-922-0204 option 3 for technical support. We would be glad to help with reloading the software from a PC.