For the accounts, Extension:User merge and delete[1] would probably be the best route, And just create a dummy account for you to merge them into. And use Extension:Nuke as Jeremy suggested to delete any pages they created.
[1]. http://www.mediawiki.org/wiki/Extension:User_Merge_and_Delete _______________________________________________ MediaWiki-l mailing list [email protected] https://lists.wikimedia.org/mailman/listinfo/mediawiki-l
