It also depends on where you want it to run. Is it a desktop (windows, mac and/or linux), a tablet or a phone (iphone, android, win7 soon and proprietary os's) or a server (linux or windows). The platform that you want to use will lead to a more limited range of choices. On the other hand (as per the previous response), if you want to use a language that you already know, that will dictate which platform(s) it can be run on.
I would like to run it on the desktop, but nothing special. I'm thinking C++, but I'm relatively new to all languages. I was thiking however, that it might be better to store the questions/answers in a mySQL database....any thoughts on that?
If your main objective is to write it in some language that's find. If what you really want is the actual tool, then you might want to consider downloading something that already works. One example is: http://www.tac-soft.com/