Which file structure would be most appropriate for codeigniter?

Answer 1

Just make your folder at the root level. Get rid of the CodeIgniter_1.7.2, you don't need that folder.

C:
  xampp (or whatever)
     www (or htdocs)
        myblog
           application
           system
           ...

For your css:

C:
  xampp (or whatever)
     www (or htdocs)
        myblog
           application
           system
           css (put your css scripts in a folder call css)
              default.css

Then to access it, just

<link href="<?php echo base_url();?>css/default.css" rel="stylesheet" type="text/css" />

To get rid of your "index.php" from your scripts, change/add a .htaccess file to the file like this. Just google a file of it and change the rewrite rule to:

RewriteRule ^(.*)$ /myblog/index.php?/$1 [L]

C:
  xampp (or whatever)
     www (or htdocs)
        myblog
           application
           system
           css (put your css scripts in a folder call css)
              default.css
           .htaccess