Quote from mbay:
FireFox is a memory hog compared to IE7, but I have been getting use to turning off my computer to go to bed. Better for the computer and healthier for you to avoid radiation.
IE 7's memory usage is better managed, but overall, firefox is still safer.
I recommend firefox 2.0 just for safety alone and alot of companies are including firefox as their default browser too.
I recommend having both and making firefox your default, but if your using a hacked version of XP, then you will not be able to install IE 7.
Avant and Maxathon are good browsers too, but I still prefer firefox.
I am still waiting for vista and to find out what are the main advantages of IE 7 with vista in 32 and 64 bit.
If you are a trader, I would recommend you avoid 64 bit for the time being and stick with 32.