Firefox buggy?

I am using Firefox 1.5.0.4 and I find that it crashes more often than the earlier version of Firefox. Wonder why.

I go to a website and click on a link to see another page and this just causes it to crash! It happens randomly with no apparent pattern. I wonder if it has anything to do with browster incapatibility with the latest Firefox? Maybe not. Just a thought, because I have the same Firefox installed on another computer with similar specs which does not crash as often.