Background Processes in Android

StoryAlbum - Never touched it to know what it is.

ChatOn - Like any other messenger service it will run in the background. It's an always on chat service, like Hangouts, Skype, etc and millions use it. It's just not that popular stateside.

WatchOn - Looks for TV show suggestions based on what you've been watching (via likes or channel changing). Will occasionally display notifications with these suggestions or reminders for a show.

Samsung Apps - Same reason Google Play always runs. App checks and all that fun stuff. Some items are available through Samsung Apps only, and not Google Play.

Samsung Link - Part of the ecosystem used for media sharing to other devices. I.E. sending pics to a PC or TV, or using your PC to browse your mobile pics.

Software Update - Can't tell ya. Not running on mine.

ELM Agent - Emulated Legacy Mount for multi-user support

Unified Daemon (EUR) - Related to background downloads, usually stock apps/widgets.

PageBuddyNotiSvc - Part of the Notification services. Some launchers can access the levels of it, allowing the disabling of individual parts of it. One is the ever annoying recommended apps that appears when you plug in headphones.