I wish to uninstall Photosmart Essentials, but am unable to do this via my Control Panel. Please tell me how to remove it, and will this removal affect my ability to print plain and simple files and photographs?
If you remove the application, then you'll lose the ability to print, enhance or scan photos. Try using Revo Uninstaller to wipe out all the app's traces in the system.
After that, try running AdwCleaner to make sure that there are no leftover rogue registry keys or toolbars in your system.