PHP set to 16, need 24, URGENT!

[alexandre_portugal]

Hi!
I'm using Xampplite, and Drupal. In order to run gallery2 I need to have php set to 24. I have 16. Someone told me to go to php.ini and change a ValueM. Where is that file?
Can someone help me with this, where can I change, and how can I change the settings? I know 0 on PHP..
Please, it´s very urgent, how is it done?

[Milligan]

[alexandre_portugal]

Thank you, thank you, thank you.
So I just have to change a something like valueM=16, that´s it? I´m not on my pc in the moment.
Thank you a lot.

[Milligan]

[alexandre_portugal]

Thank you a lot...
I´m going home to try it.