1) Download mysql 5.0 setup and then install mysql.
2) Now after installing mysql you have to configure an instance, for this go to MySQL Server Instance Configuration Wizard and Click Detailed Configuration->Developer Machine-> Non Transactional Database Only->Decision Support (DSS)/OLAP->Check Enable TCPIP Netwokring->Port 3306->Standard Character Set->Install as a Windows Service Now its time for you to give a password, you can give any password that you can easily remember but for the first time it is prefered that you should use root as a password. And then Click Execute, if you don't see any red X then its mean mysql is configured accurately.
Configuring PHP to work accurately with MYSQL
Please follow the steps to configure php with mysql
1) Go to C:\PHP folder copy the dll libmysql.dll to your C:\Windows\System32 folder.
2) Edit php.ini file that you place in C:\Windows during the installation of PHP, Open php.ini file in notepad and then find this line extension_dir = "./" and replace this line with the exact path of the extensions folder in C:/PHP which is ext, now the new path will be extension_dir = "c:\php\ext", i mentioned this step during the installation of php, if you didn't follow this step before then please do follow this important point now.
3)In the same php.ini file, please un comment two lines by removing semi-colon (;) . Find these lines extension=php_mysql.dll, extension=php_mysqli.dll and un comment both lines by removing preceeding semi-colon
4) Reboot your System
So this is the way to install and configure mysql with php