Why has my forum page changed?

Hi. I am not techy minded so need help. When I turned the forums page on yesterday I noticed the layout has changed. The discussions are all down the left hand side and there is loads of other stuff down the right hand side and even more stuff at the bottom. All this makes the discussion stuff, which I enjoy the most, much smaller and harder to read. I know I can make it bigger using my fingers and stretching it out, but how can I get it to automatically revert to the way it was? Thank you.