Hi,

You should be able to achieve a simple solution using built in Document Types.  I would create a Quiz document type and a Question document type beneath them (or multiple Question doctypes if you need majorly some different functionality)

Your Question document type could have fields like:

- Question (text)
- Answer Type (choice - single/multiple)
- Possible Answers - one idea is to use an Embedded Content-type package for the answers, and setup the control with two fields - Choice (text) and Is Answer (checkbox).  You could add all your choices here and check the one that is correct.

You could then use Templates & XSLT (or Razor or C#) to list out the questions, and retrieve their choices/answers pretty easily.

If you wanted more flexibility/validation on the Possible Answers you could write a customized content editor (called a datatype) as you mentioned.  There are a few different ways to do this, but the simplest is using the usercontrolwrapper:

http://www.nibble.be/?p=24
http://www.nibble.be/?p=97
http://umbraco.com/help-and-support/video-tutorials/developing-with-umbraco/data-editors/creating-a-custom-datatype-using-the-usercontrol-wrapper

There's also a blog post about creating quizzes with Contour, in my opinion it's a little too much for the content editor though.  http://www.nibble.be/?p=83

Hope this helps,
Tom