Change the number (60) in this line to whatever you want it to be set at.
PHP Code:
$maxchars='60'; // thread title length
Yes, put it in the same spot as his code. Let me know how it works for you.
As far as removing the hack goes, go into your Admin CP and run settings.php (like this:
http://yoursite.com/forum/admin/settings.php) and you should find the two areas to delete in there. It will take care of the queries needed to delete those.