If you want to disable a third party app from running much like you would on a Windows Mobile Safe Mode launch you can do so by enabling the Blackberry Storm Safe Mode option.
1. Start by taking out the battery on your Blackberry Storm and reinserting it.
2. When you see the LED light turn from red to nothing hold down your Escape Key as your device loads.
3. Eventually a dialog box will show up, press the OK button.
You should at this point see a status message showing that you are in safemode, if you don't see that message try again until the message appears.
To get back into regular mode simply remove the battery and reinsert it then turn the device on without touching anything.