The math question ‘captcha’ is a permission that you can set to allow users to bypass. Turn on the option to bypass it on the permission sets that you are using where desired. It can be found in the ‘Moderation’ section.
On the statistics you will need to make a small edit to a Simple:Press theme template. In this case the spFoot.php template found in the /templates folder of the Simple:Press theme you are using.
Locate the ‘stats’ section – shown with a comment and begins with a sp_SectionStart() function call. Before that call to sp_SectionStart() add the following line of code:
if ( $spThisUser->admin ) {
and then at the end of that block and after the call to sp_SectionEnd() place the closing bracket }
This will ensure that only admins can see the stats section. Pleaes do ensure you use this code exactly as shown.
As always we recommend that you create your own SP theme so that any customisation is not lost during a future update. (http://codex.simple-press.com/codex/themes/theme-basics/creating-a-theme/)