Acronis true image (Awesome program) is a lot like Ghost,. both are used fro full system back ups, and are NOT the best choice for data back up..
Certainly they are the farthest thing from a solution intended to back up a single directory. (for those interested a free app that works similarly, though less robust and intuitive) is "Bart PE")
Among the myriad back up programs out there, the one I find that stands out in unique functionality dept. is "Mirror Folder"
As the name implies, it is used to mirror specific folders or directories. It can be used to do so in "real time" with a software based RAID that will tackle entire drives or specific folders, or it can be used to do incremental mirroring at scheduled times, or when external backup media is detected and present.
Very flexible tool.
Now, what I am still looking for is an automated incremental/differential back up program that saves it's destination to 4GB DVD ISO files! 