I have an older Dell inspiron laptop that I mainly use for light surfing and email while at home. It is running XP SP3 with 2GB RAM

in the last couple of weeks Firefox (21) has been crashing more and more until I can hardly go 5 minutes without it crashing. I have tried various fixes to no avail.
I thought maybe it was Flash causing the problem and disabled the flash add-on. That worked for a day or two and then it started again. I've run malwarebytes and other utilities and nothing was found.

I decided to try Chrome but it suffers from the same thing only more frequently.

I am starting to get pi$$ed off

Any Ideas?

Thanks in advance