1and1 installation of pro version

Hello, I'm new to wordpress at all. My blog is hosted by 1and1. They have a installer in the package that I used to install the catchbase template. If I upgrade now, how do I update my package there? I have no idear how to this manually and I think it is not a good idear. I don't like to crash my site. Second question. Is there any difference between the free version I have and the pro version? I would like to replace the footer line where it refers to Catchbase themes. Greetings Ralf