macbook issue

so a few days ago I became fed up with my macbook. every time I would launch firefox, firefox would crash. every time I would launch chrome, the fonts in chrome would get screwed up as if the encoding was messed up (the encoding was not messed up though.

so I did a clean sweep of OS X. reinstalled OS X 10.5.8 and everything worked fine the past few days. firefox started crashing again.

can anyone help?