Php session settings

Hi all, I am new to PHP this is my second post to this group. I have tried using the following CMS systems on my web server (remote) Joomla CMS made simple Phpwebsite And more recently Coppermine photo album All of these apps use PHP heavily. None of these apps seem to run very well and they all require constantly refreshing the browser. When I installed "CMS made simple" (nice install program) it checked for MySQL database, permissions etc. everything passed the test but it flagged low memory allocation as a possible problem. The install succeeded but the program indicated that performance would be poor or crippled. My hosting service allows me to add a customized php.ini in the same folder as the app. I know nothing about php.ini so I was hoping someone could point me to which of the many settings would be best to tweak. Any help would be much appreciated Thanks, Jeff Quick recap: constantly refreshing browser, could tweak php.ini, total newbie, no hair left to pull out.