If all you're using it for is storage, then you can get away with not installing SmartWare, or uninstalling SmartWare if it's already installed.
The MyBook Essential drives work fine as plain ol' drives. I'm using 4 that way at the moment.
SmartWare is essentially a backup manager. But it's selective in which of your user files it backs up... it's not a "system backup" tool.
People who want to back up their photos are happy enough with it. Anyone using the drives for full backups, uses other programs, and anyone using the drives just as drives, just accesses them from Explorer or the file requesters in any application.
The "SES Driver" is for the communications channel between the drive and the PC. The drive will work as a drive without the driver installed, but you'll keep getting the nags to install the driver every time you attach the drive. In this case it's used for the password functionality and for the little LEDs that show how full the drive is. You're fine updating the driver so that Windoze will stop bugging you about the update it has found.