This question dates from the D6 days. These days, for D7, "there is a module for it", which IMO does what you're looking for, and actually much more, as further detailed below: the Answers module. Here are some details about it (from its project page):
Answers enables the implementation of a Question & Answer system in a Drupal site. Users can post questions and other users can answer them.
Head over to its project page for more details.
At its core, this module exists of 2 typical content types:
The "Best Answer" submodule can be used so that the question author can "accept" one of the answers as the best one. And you could make the Rules module to either trigger all sorts of subsequent things to happen "when an answer gets marked as best answer", or to add all sorts of validations when posting an answer (or question).
The Answers module comes with integrations with other modules such as the Rules module and the Userpoints module and supports voting.
Have a look at the (new) demo site of the Answers module. This link shows various menu options within the block with title Answers Menu, i.e.:
- Questions (= a view):
- All: of all existing questions (= default tab).
- Answered: all questions which have a "best" (= accepted) answer (= sub-tab).
- Unanswered: all questions which do not yet have a "best" (= accepted) answer (= sub-tab).
- Answers (= a view): lists all existing answers for any of the existing questions and which does not (yet) have any submenu options (implemented as tabs).
- Rankings (= a view): contains a list of users with their actual ranking (= reputation points implemented via user points), and with each user a link to either the questions or answers from that user.
- Ask Question: to post a new question (the equivalent of
node/add/question), which is only shown for authenticated users though.
These views also use the dataTables format, but you could easily replace that with any views display format you'd want. And because of the search box that comes with dataTables, there is no need for extra menu links to search within questions, answers or rankings.
These new/enhanced views were created starting from the 7.x-4.x-rc2 release of Answers, and will be included in the next release of it also (together with various other enhancements not yet visibile in the demo site).
To decide between the 7.x-3.2 and the 7.x-4.0-rc2 release, I would recommend the 7.x-4.0-rc2 . Even though it is not yet an official release, it is fairly stable/functional, and only has a few more minor glitches to be resolved. Pretty soon an rc-3 (the last 'rc' release?) should become available also, which will include the newest features as you can see in the demo site already.
Disclosure: I'm a (co-)maintainer of this module.