I repeated steps 7 and 8 as you said but it didn't work. Using my ftp, I uploaded all the files in the WordPress 2.5.1 folder except the license.txt and readme.html files. During upload, sometimes my ftp software would ask me if I would overwrite the files with the newer one and I chose "overwrite all if newer". After the upload completed, I went to upgrade.php on my site and clicked "continue" to finish the upgrade. I logged in to my dashboard, but it still looked the same just as how it was before I repeated the upgrade.
Here's a screenshot of my dashboard: