Geeklog Forums

Hi!I've installed geeklog into my admin cp,but i'm a little comfussed...
Well,the first website i made before 2 years it was,and it's still a static website and ALL pages are static.So,via an ftp server and a progamm i modify pages and save them to remote server.But now,i need to build a big community so i desided to install a cms application because i really haven't any idea of php language.So,i'd like to ask the forum,two things..
1)I want to put an existing html file (theme) for my dynamic website into geeklog,and someway modify it so i can get the result i need.Can i do this action,and if i can,how?...
2)Do i need to start learning the advanced of php so i can make the website for my own,or the geeklog "slogan"-"You just have to know html" trully exists?If i don't have to learn the whole php how can i procced,and if i don't,is there any other way to do my second action?
These are..more than two questions,so if everyone knows at least ONE please let me know..
Many thnxz,Ntinos!