I actually changed the password while using phpmyadmin.
did you select password in the function drop down box when editing the
entries? passwords are not stored in clear text.
but please, like tat said, check your ports and the bind-address in
my.cnf.
if you really messed up your root password and you have no write access
to the mysql database, there comes no way of rescuing to my mind than
back up the database files, install again and copy them over to the new
installation, except the old mysql database. but there are probably
better ways to fix this.