No browser will prevent stupidity. Anyone who surfs unprotected WILL end up with something that won't wash off in the shower.
IE is not idiot-proof... but neither is Firefox or Opera. It all falls back to the user, period.
I use Firefox due to the customizability factor. I also use IE Tab in Firefox, and use IE on occassion (mainly at work). I have tried Opera, but it wanted to take over which ain't good with the fat man.