If your BlackBerry Bold 9000 series device is frozen or not responding, you will probably want to reset the unit. Here are the different types of resets that can be perfomed in the order they should be tried.

Soft Reset
Press ALT + RIGHT SHIFT(CAP) + DELETE.

Double-Soft Reset
Press ALT + RIGHT SHIFT(CAP) + DELETE . The screen will go blank for a few seconds. When the screen comes back on, immediately press ALT + RIGHT SHIFT(CAP) + DELETE again.

Hard Reset
If none of the above works, pull the battery out of the unit for a few seconds, then reinsert it.