Assuming you're in Q2A 1.4, use $QA_CONST_PATH_MAP in qa-config.php to map the questions or unanswered page to the home page, for example:
$QA_CONST_PATH_MAP=array(
'questions' => '',
);
Then, if necessary, you can change the default sort order in qa-page-questions.php by adding this line before switch ($sort):
if (!isset($sort)) $sort='views';
You'll also need to change qa_qs_sub_navigation() in qa-app-q-list.php to add an explicit sort parameter onto the 'recent' item, like in the other items.