Joomla admin password is stored in mysql, so it can be changed easily by running a simple mysql query.
If you have a cPanel account, use the phpMyAdmin to reset the password. Select the Joomla database and run the following query.
UPDATE `jos_users` SET `password` = MD5(‘newpass‘) WHERE `jos_users`.`username` = “admin” ;
“newpass” – replace this with the new password you wish to use.
“admin” – replace this with your username.
and submit the query.Now you should be able to login to Joomla admin page with the new password.
How can I move all the files from that folder to the main directory without damaging or changing anything?
Moving the Joomla files and folders up one level will not damage them. You will need to edit your configuration.php file in a text editor to remove the joomla folder from the path for your tmp and log folders. You may also need to rename the welcome.html file to welcome.old or just remove it from your root folder.
If you are using Jooma 1.5.x no configuration file changes should be necessary. You can simply move the files to the new location.
If you are using 1.0.x then you will need to edit the configuration.php file.