need fast help

[numanx]

Hi there why i recieve this error???

Warning:  mail() [function.mail]: Failed to connect to mailserver at "localhost" port 25, verify your "SMTP" and "smtp_port" setting in php.ini or use ini_set() in C:\xampp\htdocs\takeinvite.php on line 75

Warning:  Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\takeinvite.php:75) in C:\xampp\htdocs\takeinvite.php on line 77

I know i have a localhost i don`t want a prof host.
And how i can solve it......

I have another problem someone is trying to hack me but i changed the config.inc in the localhost server xampp another way to hack is??? diferent by accesing the beginers phpmyadmin