Jg51_mission.dll and DynamicCampaign.dll are part of user campaigns, so if you have both campaigns running you shouldn't delete them
The campaigns.ini.bak is a Backup file, may be you have installed a campaign with its own installer, so the installer manipulate the campaigns.ini and created the backup file.
You should take a look at
http://forum.1cpublishing.eu/showthread.php?t=23908
this tool makes campaign installing much easier.