I use a incremental backup program for my data. Incremental meaning that it replaces changed files, add new files and deletes to the backup drive. Hence it updates very quickly.
And I backup one master folder which contains all of my data and contains many folders and files (GBs of data). The backup is the same file structure and I can easily check/copy any files on it.
I keep separate copies of the OS and programs.
Be careful thinking you can back up a image to a changed or new computer. Lots of changes might be required for the OS and/or drivers making a image restore less than successful.