Q: Backup size says 2.0 GB, but I have all backup options turned off. Why is my backup size still 2.0 GB?

I had an iPhone 4 updated to the iOS 7.1.2 version, and I recently purchased an iPhone 5s. When I got the 5s, I transferred all of my camera roll pictures from my 4 to my PC in a file folder and deleted all the photos from my 4 camera roll. I also turned off the "camera roll" backup option in my iCloud storage settings. However, my backup size still said I had a large backup size, so I turned off all the apps in the backup options under the iCloud storage tab. Along with all the apps, I turned off the backup for the Mail, Contacts, Calendars, Reminders, etc. Yet, my backup size on my 4 still said 2.0 GB, and my 5s needs more backup storage without purchasing any extra storage.

I'm not sure if I should completely delete my 4 backup or if there is a solution without completely deleting its backup. If there is a possible solution to decrease my backup size without deleting the backup, what is that solution? If deleting the 4 backup is the best option, what are the "risks" of deleting the backup? Like would I lose anything I restored onto my 5s from the 4 backup, etc.?