When I play quizzes I use the TAB button to go to the next question in Internet Explorer and the up and down arrows to choose between the multiple choice options in each question.

But in Netscape and Firefox browsers the TAB button in a quiz will take me to the next option and not the next question and the up and down arrows don't work.

The TAB button is especially useful during the timed-quizzes and also handy when playing quizzes normally.

Is it possible to change this in Netscape and/or Firefox so it works like IE?

I'm guessing this cannot be changed. It doesn't matter, I'll get to used to it on Firefox anyway. It's a just a handy tool to have whilst playing quizzes and less of an annoyance, since I prefer using the keyboard rather than the mouse.

I can go to IE as well but Firefox is the best so I'll get used to it on here.

In Internet Explorer Shift+Tab will take you back to the previous question instead of the next. Maybe a similar combination exists for Firefox that will make you go to the next question instead of the previous?

Shift+Tab also takes you back to the previous question in Firefox. I haven't found one that takes you to the next quesion yet but Shift+Tab is quite useful.