You might get better answers if you provide more information such as when this started happening. For example, did you add a new account recently? Install any applications recently?
Normally, when weird stuff happens on OS X such as crashes, repairing permissions can be a good place to start. Try opening Disk Utility and select your computers Hard Drive on the left hand side, then click 'Repair Permissions'. This will take a few minutes and may solve your problem. Try a restart after the repair before you go back into Accounts.
Have you tried this under a different user account? I've come across instances of people having this only occur on one account. You could create a new account and restore documents etc from a backup.