The good news is that I can log into the dashboard at http://www.managemagicjack.com. Unfortunately, when I click on 'Plugins', I'm sent to wp-admin/install.php - and WordPress reports it can't find that file. The same thing happens when I click on 'Dasboard'.
I tried renaming the plugins directory to take them out of the equation, I changed the permissions for .htaccess to 666 to see if that would un-jam the works and double checked wp-config (but all pages are visible, so that connection seems OK). I checked the database tables in phpMyAdmin (all showed OK), and repaired the Options table for grins and giggles.
Any other links in the Dashboard seem to be OK, but it's difficult operating without access to the Plugins page. Does anyone out there have any scathingly brilliant ideas? Thanks for your thoughts!