looking in the forum I found a message saying that apache2-mod-php5 already configured by default to handle php.
So I tried again and it work (it must have somthing went wrong in the first installation).
ok, the admin panel start after configuring the database, but the index page of the blog does not appear, instead I see the list of files in the directory where is index.php.
Coincidentally after I restart xorg, and instead of the admin panel I saw a completely white page.
Now I'm using xamp.scm and it operates completely (even if I had to change the permissions on the wordpress directory to guarantee all the privileges, it is insicure), I guess the problem is in some configuration files.
Maybe I'll make a diff (which configuration files might be interested?)