So... what's the question?
Also, do you have error_reporting set to E_ALL (or better) and display_errors set to On? (Check [man]phpinfo/man if you aren't sure.) If PHP can't open the include()'d files, it will emit an error. If something is going wrong inside those include files, PHP will emit an error.
If you're outputting incorrect HTML in those include files... well, your web browser should emit an error for that one, but we can't help you with that since a) you haven't shown us the contents of those include files, and b) you haven't given us enough information about what the problem is.