Mysql serveur ne démarre plus

Bonjour,
J'essaye depuis quelques jours de relancer mon serveur mysql mais rien à faire, ça ne démarre pas.
J'ai essayé plusieurs trucs en passant même par la désinstallation. toujours est il que j'ai besoin de votre aide. et je remercie déja ceux qui vont s'y coller.
je travaille sous debian lenny et voila ce que j'ai lorsque j'essaye de démarrer le serveur.

vaio:/home/christian# /etc/init.d/mysql start
Starting MySQL database server: mysqld . . . . . . . . . . . . . . failed!


et voila ce que j'ai lorsque je tente un passage par le terminal


vaio:/home/christian# mysql -u root -p
Enter password:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)



vaio:/home/christian# vim /var/log/daemon.log
May 28 11:26:29 vaio mysqld[7205]: 090528 11:26:29 [ERROR] Can't start server : Bind on unix socket: Permission denied
May 28 11:26:29 vaio mysqld[7205]: 090528 11:26:29 [ERROR] Do you already have another mysqld server running on socket: /var/run/mysqld/mysqld.sock ?
May 28 11:26:29 vaio mysqld[7205]: 090528 11:26:29 [ERROR] Aborting
May 28 11:26:29 vaio mysqld[7205]:
May 28 11:26:29 vaio mysqld[7205]: 090528 11:26:29 InnoDB: Starting shutdown...
May 28 11:26:31 vaio mysqld[7205]: 090528 11:26:31 InnoDB: Shutdown completed; log sequence number 0 43655
May 28 11:26:31 vaio mysqld[7205]: 090528 11:26:31 [Note] /usr/sbin/mysqld: Shutdown complete
May 28 11:26:31 vaio mysqld[7205]:
May 28 11:26:31 vaio mysqld_safe[7235]: ended
May 28 11:26:43 vaio /etc/init.d/mysql[7365]: 0 processes alive and '/usr/bin/mysqladmin --defaults-file=/etc/mysql/debian.cnf ping' resulted in
May 28 11:26:43 vaio /etc/init.d/mysql[7365]: #007/usr/bin/mysqladmin: connect to server at 'localhost' failed
May 28 11:26:43 vaio /etc/init.d/mysql[7365]: error: 'Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)'
May 28 11:26:43 vaio /etc/init.d/mysql[7365]: Check that mysqld is running and that the socket: '/var/run/mysqld/mysqld.sock' exists!
May 28 11:26:43 vaio /etc/init.d/mysql[7365]:

Merci d'avance