Judging by your questions, you are new to WordPress. That's cool. Just relax and take it one step at a time.
1) above it are 4 sidebars. You can change that number. There is demo info in there right now. If you go to widget areas, you will see the four footer sidebars. Just drag and drop the widgets you want to show in each of the columns to change them.
2) Those are Widgets. Find them in the backend and assign the ones you want by first dragging and dropping them and then opening each widget to customize it.
3) If you want, you can download Notepad++ (google it) and search the entire theme directory for that phrase and you will find it.
4) You are explaining things too abstract for us to follow. What pictures? What page are they located on. What text? Please give URL and put in quotes what text you are talking about in order for us to help.
Please remember that you have to do the footwork and learn wordpress first so that you can help yourself most of all. I suggest you look on youtube about basics of wordpress and watch 2 hours worth of videos to get a better understanding of what are widgets, sidebars, where to find them, etc.