"php5" is extremely generic. And, as far as I know, the PHP authors have never distributed a "php5" version. They all have at least two digits in them, usually separated by periods. And, yes, the actual version number IS important. I wouldn't have asked otherwise.

And, if phpinfo is finding the master and local values to be blank, then that means you're either not editing the correct php.ini file, or you've neglected to restart the webserver services since making the changes. And, since Zen Cart is using the same information that phpinfo is revealing, Zen Cart is perfectly correct in telling you that the date.timezone setting is not set.

You can get specific help on learning how to configure your local webserver services from the various vendors of the webserver apps you've installed. Once you've sorted that out, then you can carry on with installing Zen Cart.