Problems after installation…

I have a number of issues after the Wp guys installed my blog for me…

There are two main pages… http://www.myblog.de/ AND http://www.myblog.de/?p=0. Only the second page actually shows any changes I make in the cotrol panel.(themes, etc)

Also: I cannot comment on posts. when I hit send, opera hangs up on http://www.myblog.de/blog/wp-comments-post.php
and the comment is not saved.

I imported posts and comments from a previous blog, but the categories do no show a counter on the number of post under that category.

Are these issues related?

Please help, I am COMPLETELY new at this…