I just installed Firefox 3.6.4 on my Mac Mini (Snow Leopard) and then updated flash. In doing so, Firefox crashes each time I try to open it :( Going to use

I just installed Firefox 3.6.4 on my Mac Mini (Snow Leopard) and then updated flash. In doing so, Firefox crashes each time I try to open it :( Going to use Chrome though I prefer to use Firefox. Any others experience this? Is there a fix - thnx