Just trying to install and get the following warnings

1. PHP magic_quotes_gpc [is enabled]
   Warning!
   You should consider disabling magic_quotes_gpc. For more information See #25 of the Zenphoto troubleshooting guide.

I've looked in HT access and magic_quotes_gpc doesn't exist,can anybody help to find it in php

2)PHP mbstring package [Your internal characater set is ISO-8859-1]
Warning!
Setting mbstring.internal_encoding to UTF-8 in your php.ini file is recommended to insure accented and multi-byte characters function properly.

How do I change this

You have to either edit your php.ini or change that via .htcaccess, if your host allows you to do so at all. If unsure contact your host.