Hello saeed,
Regarding your questions,
1) How often you want to restart the httpd and mysql ? If you want to restart them every hours, you need to create a script, like on below,
#!/bin/sh
/etc/init.d/httpd restart >/dev/null 2>&1
/etc/init.d/mysql restart >/dev/null 2>&1
Save the file and give it execute able permission, by issuing chmod +x filename
To restart the services at different intervals, I will write a howto.
2) It depends on the server and the control panel you have. The answers below assumes your control panel is Cpanel. Also I didn't fully understand your second question. If you are looking for the statically compiled modules, execute the following command at your server.
/usr/local/apache/bin/httpd -l
And if you would like to compile a new module having APXS support the location of apxs is /usr/local/apache/bin/apxs , all dynamically loaded modules can be seen by opening up the /usr/local/apache/conf/httpd.conf and searching for 'LoadModule' keyword / directive.
3) You can..You either have to write your custom script or use already available ones lile the System Integrity Monitor (SIM) .
Hope this helps,