OK, I used BackupBuddy to save everything so should be fine.
Not to be overly direct but please make sure you can restore your backup even if you don't have access to BackupBuddy.
Proceed at your own risk! You could lose everything on your WordPress installation if you make a mistake!
There, that's out of the way. :)
That said, go into phpMyAdmin and locate the tables (they're not files) like I described. Select those _1_ tables and use the option to drop them.
I don't use phpMyAdmin (I'm more of a CLI person myself) so I can't provide you specifics on how to do that. Read up on phpMyAdmin and give it a go if you feel comfortable with it.
And once again, if the Really Bad Thing™ happens then restore your backup and start from the beginning.