Uninstall it and reinstall it.
When I open mozilla I get, firefox.exe has encountered a problem and needs to close. What's going on I tried restarting my computer and it's still doing it. I have windows xp and I don't know what version of firefox I'm using I think it's the latest version.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic