I used lots of plugins too with FF, but when I had opened 275 tabs, the extensions could not handle it started to crash the FF.
I skipped Vista completely
I loved the AdBlock (now I use only extension AdBlock on chrome), some ext. that saves page as PDF,jpg,tiff,- not available on chrome the same way it worked on FF(for that I use Fast stone capture), with out sending it to the home server first and than back to me- unsafe and need internet and slowww.
Other than that I did not have crashes - maybe Flash Player kept crashing too.