explorer.exe, firefox, and internet explorer will not start

[Snoof.Mail]

My Windows XP system has slowly been getting worse. At first, IE and
Firefox would not open. When I looked at the task manager, they were
opening and quickly shutting down. Recently, explorer will not load,
not even from the task manager or Safe Mode. My ZoneAlarm firewall also
fails to load at startup, as well as Google Talk and other programs
that load at startup. How should I go about to try and fix this issue?

 

[DL]

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